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Typical modern agricultural barbed wire
Barbed wire, also known as barb wire (and frequently in dialect form spelled bob or bobbed), is a type of fencing wire constructed with sharp edges or points arranged at intervals along the strand(s). It is used to construct inexpensive fences and is used atop walls surrounding secured property. It is also a major feature of the fortifications in trench warfare (as a wire obstacle).

A person or animal trying to pass through or over barbed wire will suffer discomfort and possibly injury. Barbed wire fencing requires only fence posts, wire, and fixing devices such as staple. It is simple to construct and quick to erect, even by an unskilled person.

The first patent in the United Statesmarker for barbed wire was issued in 1867 to Lucien B. Smith of Kent, Ohiomarker, who is regarded as the inventor. Joseph F. Glidden of DeKalb, Illinoismarker, received a patent for the modern invention in 1874 after he made his own modifications to previous versions.

Barbed wire was the first wire technology capable of restraining cattle. Wire fences were cheaper and easier to erect than their alternatives. (One such alternative was Osage orange, a thorny bush which was time-consuming to transplant and grow. The Osage orange later became a supplier of the wood used in making barbed wire fence posts). When wire fences became widely available in the United Statesmarker in the late 19th century, they made it affordable to fence much larger areas than before. They made intensive animal husbandry practical on a much larger scale.


A selection of forms of historic and modern barbed wire

Barbed wire has a multifaceted historical context that began in the in mid 19th century Europe, but primarily occurred in The United Statesmarker and can be divided into two time periods. The first being before the concept was even demonstrated or thought of on such a large scale as the second time period from 1873 onward demonstrates. The second historical part also considers how the barbed wire industry grew and later impacted farming and ranching life in the Western United States and later the world.

Before 1873

It is often overlooked, but it was in Francemarker that the first person to propose a fencing type consisting of flat and thin wire was in France by Leonce Eugene Grassin-Baledans in 1860 and consisted of bristling points, making this fence difficult to cross. Louis Francois Janin later proposed a double wire that held diamond shaped barbs made out of metal material in April 1865 and received a patent for his proposal. Michael Kelly from New York shared a similar idea to Janin, but proposed that the fencing should be applied for the specific purpose of deterring animals. More patents followed, and in 1867 alone, there were six patents issued for barbed wire, and only two of them addressed livestock deterrence, one of which was from American Lucien B. Smith of Ohio.Before 1873, the U.S. was moving westward because of recently acquired lands from the Louisiana Purchase that later led to the Plains Indians Wars, solidifying America’s territorial dominance over this great Central Expanse. Ranchers moved out on the plains, and a need was created to fence their land in against encroaching farmers, other ranchers, and railroads throughout the West, creating a desire for property delimitation. Additionally, farmers needed to keep stray cattle from trampling their crops, so it was also in the best interest of this group to find a sturdy barrier. Traditional fence materials used in the Eastern U.S. like wood, stone, and hedging were not reliable in the rain starved dusty soils, so a more cost effective alternative was needed to make the cattle operations more profitable for both ranchers and their investors back in the Eastern U.S.

The 1873 meeting and Initial Development

The first of the big four in barbed wire was Joseph Glidden, who at that time was a farmer in 1873, and is often credited for refining the successful barbed wire product, but let others popularize it for him. Glidden initially came up with his idea for a sturdier fence, because of a display at the 1873 fair in DeKalb Illinois by a man named Henry B. Rose. Rose had patented “The Wooden Strip with Metallic Points” in May 1873. The invention was simply wooden block with wire protrusions designed to keep cows from breaching the owners’ fence. That day, Glidden was accompanied by two other men the first of was Isaac L. Ellwood a hardware dealer and the second was Jacob Haish a lumber merchant, both of whom shared Glidden’s drive to create a more durable wire that contained fixed barbs. Glidden experimented with a grindstone in order to twist two wires together to successfully hold the barbs on the wire in place which were created from experiments with a coffee mill from his home. Later Glidden was joined by Ellwood who knew his design couldn’t compete with Glidden’s which he applied for patent in October 1873. Meanwhile Haish, who had already secured several patents for barb wire design in the interim already applied over a week before Glidden for a patent on his third type of wire, the S barb and charged Glidden for interference, pushing Glidden’s approval for his patented wire nicknamed “The Winner” back until November 24, 1874. Barbed wire production greatly increased with Glidden and Ellwood’s establishment of the Barb Fence Company in DeKalb Illinois following the success of The Winner. The company’s success attracted the attention of the Vice President Charles Francis Washburn of Washburn & Moen Manufacturing Company, which was a very important producer of plain wire in the Eastern U.S. Washburn visited De Kalb and convinced Glidden to sell his stake in the Barb Wire Fence Company, while Ellwood stayed in DeKalb and renamed the company I.L Ellwood & Company of DeKalb.

Promotion and Consolidation

John Warner Gates of Illinois entered the scene in the late 1870s to promote the successful product in the highly lucrative markets of Texas which were initially hesitant to adopt the wire because fears that cattle might be harmed, or that the North was somehow trying to make profits off the South. There was also heated debate between the farmers who wanted fencing and the ranchers who were losing the open range. Barbed wire ended up prevailing through demonstrations in San Antonio in 1876, with Gates showing that the technology could keep cattle contained, leading sales to increase dramatically in the years to follow. Gates eventually parted company Ellwood and branched off on his own become a barbed wire baron himself. Throughout the height of barbed wire sales in the latter half of the 19th century, Washburn/Ellwood, Gates, and Haish competed with one another, with Ellwood and Gates eventually joining forces to create the American Steel and Wire Company later acquired by The U.S. Steel Corporation. Between 1873 and 1899 there were many companies, as much as 150 manufacturing barbed wire to cash in on the insatiable demand in the West, but there were also many investors interested in the wire because of its low capital investment requirements and the ability for almost anyone with enough determination to manufacture a new wire design for profit. Between these time periods, there was also a sharp decline in the amount of firms engaged in wire production, with most being consolidated into larger wire producing companies, the most visible being the American Steel and Wire Company, formed by the merging of Gate’s and Washburn/Ellwood’s industries. Smaller companies were wiped out because of economies of scale costs and the smaller pool of consumers available compared to the larger corporations. The American Steel and Wire Company established in 1899 was a good representation of vertical integration, controlling all aspects of production from producing the steel rods to making many different wire and nail products from the same steel, although later part of U.S. Steel, the production of barbed wire would still be a major source of revenue for years to come.

Barbed Wire and Conflict in History

In the American West

Barbed wire emerged as a major source of conflict in the U.S. West with the so called “Big Die Up” incident in the 1880’s. This conflict occurred because of the instinctual migrations of cattle away from the blizzard conditions of the Northern Plains to the Warmer and plentiful Southern Plains, but by the early 1880’s this area was already divided and claimed by ranchers. The ranchers in place, especially in the Texas Panhandle knew that their holdings could not support the grazing of additional cattle, so the only alternative was to block the migrations with barb wire fencing. Many of the herds were decimated in the winter of 1885 with some losing as many as three-quarters of all animals when they could not find a way around the fence. Later other smaller scale cattlemen, especially in central Texasmarker, opposed the closing of the open range, and began cutting fences to allow cattle to pass through to find grazing land. In this transition zone between the agricultural regions to the south and the rangeland to the north, conflict erupted, with vigilantes joining the scene causing chaos and even death. The fence cutters war came to an end with the passage of a Texas law in 1884 that stated among other provisions that fence cutting was a felony, and other states followed although conflicts still occurred through the opening years of the 20th century.

In War

Barbed wire also became extensively used in war efforts like the Boer War, where it played a strategic role bringing spaces under control. More significantly, barbed wire was used extensively in World War I, where it was used as an effective tool to prevent motion with deadly consequences. Barbed wire entanglements were placed in front of trenches to prevent direct charges on men below contributing increasingly to a war fought by man against machines. The barbs on the wires themselves also displayed noticeable differences, the most noticeable being that they were much closer together forming an often continuous sequence. Barbed wire was effectively able to weather most heavy bombardments because it could be easily replaced, and its structure consisted of so much open space that machine guns rarely destroyed enough of it to render its purpose obsolete. Eventually, barbed wire was overcome by the production of the Tank in 1916 shown by the Allied breakthrough at Amiensmarker through German lines in August 8, 1918.

In Concentration Camps

In the 1930’s and 40’s Europe the Nazis used barbed wire in concentration camp architecture, where it usually surrounded the camp and was electrified to prevent escape. Barbed wire served the purpose of keeping humanity contained and was a cheap, easy to install, and deadly at the same time. Additionally, different nationalities were separated, men and women were separated, and working nationalities like Jews and Ukrainians were separated within the camps walls. Infirmaries in extermination camps like Auschwitzmarker where people were gassed or experimented on were often separated from other areas by electrified wire and were often braided with branches to prevent outsiders from knowing what was concealed behind their walls.

Modern Day Uses

Barbed wire continues to be used today as a means of division in areas as diverse as South American rainforests dividing large landowner’s holdings from those of natives, to the U.S./Mexico border where it composes portions of the fence separating the countries. Additionally barbed wire is used to divide Israel from the Palestinian territories, while also delimiting refugee camps in areas like Lebanon, Syria, Jordan, and Kosovo. Detainees from Camp X-Ray in Guantanamo Bay Cuba are also fenced in and currently contained by barbed wire.

In the United States Southwest

John Warne Gates demonstrated barbed wire for Washburn and Moen in Military Plaza, San Antonio, Texasmarker in 1876. The demonstration showing cattle restrained by the new kind of fencing was followed immediately by invitations to the Menger Hotelmarker to place orders. Gates subsequently had a falling out with Washburn and Moen and Isaac Ellwood. He moved to St. Louismarker and founded the Southern Wire Company, which became the largest manufacturer of unlicensed or "bootleg" barbed wire. An 1880 US District Court decision upheld the validity of the Glidden patent, effectively establishing a monopoly. This decision was affirmed by the US Supreme Courtmarker in 1892. In 1898 Gates took control of Washburn and Moen, and created the American Steel and Wire monopoly, which became a part of the United States Steel Corporation.

This led to disputes known as the range wars between free-range ranchers and farmers in the late 19th century. These were similar to the disputes which resulted from enclosure laws in England in the early 18th century. These disputes were decisively settled in favor of the farmers, and heavy penalties were instituted for cutting a barbed wire fence. Within 25 years, nearly all of the open range had been fenced in under private ownership. For this reason, some historians have dated the end of the Old West era of American history to the invention and subsequent proliferation of barbed wire.

Agricultural fencing

Classic barbed wire
Classic barbed wire
Barbed wire fences remain the standard fencing technology for enclosing cattle in most regions of the US, but not all countries. The wire is aligned under tension between heavy, braced, fence posts (strainer posts) and then held at the correct height by being attached to wooden posts and battens, or steel star posts. The gaps between star posts vary depending on terrain. On short fences in hilly country they may be placed every , while in flat terrain with long spans and relatively few stock they may be spaced up to 30 to . Wooden posts are normally spaced at 2 rods (10 m) in any case with 4 or 5 battens in between. Many farmers place posts 2 meters apart as battens can bend causing wires to close in on one another.

Barbed wire for agricultural fencing is typically available in two varieties—"soft" or mild-steel wire and "high-tensile". Both types are galvanized for longevity. High-tensile wire is made with thinner but higher-strength steel. Its greater strength make fences longer lasting because cattle cannot stretch and loosen it. It copes with the expansions and contraction caused by heat and animal pressure by stretching and relaxing within wider elastic limits. It also supports longer spans, but because of its "springy" nature it is hard to handle and somewhat dangerous for inexperienced fencers. Soft wire is much easier to work but is less durable and only suitable for short spans such as repairs and gates, where it is less likely to tangle.

In high soil-fertility areas where dairy cattle are used in great numbers 5- or 7-wire fences are common as the main boundary and internal dividing fences. On sheep farms 7-wire fences are common with the second (from bottom) to fifth wire being plain wire. In New Zealandmarker wire fences must provide passage for dogs since they are the main means of controlling and driving animals on farms.


Barbed wire fence in west Texas
As with any fence, barbed wire fences require gates to allow the passage of persons, vehicles and farm implements. Gates vary in width from to allow the passage of vehicles and tractors, to on farm land to pass combines and swathers.

Gates for cattle tend to have 4 wires when along a three wire fence, as cattle tend to put more stress on gates, particularly on corner gates. The fence on each side of the gated ends with two corner posts braced or unbraced depending on the size of the post. An unpounded post (often an old broken post) is held to one corner post with wire rings which act as hinges. On the other end a full length post, the tractor post, is placed with the pointed end upwards with a ring on the bottom stapled to the other corner post, the latch post, and on top a ring is stapled to the tractor post, the post is tied with a Stockgrower's Lash or one of numerous other opening bindings. Wires are then tied around the post at one end then run to the other end where they are stretched by hand or with a stretcher, before posts are stapled on every , often this type of gate is called a Portagee Fence or a Portagee Gate in various ranching communities of coastal Central Californiamarker.

Most gates can be opened by push post. The chain is then wrapped around the tractor post and pulled onto the nail, stronger people can pull the gate tighter but anyone can jar off the chain to open the gate.

Human-proof fencing

Most barbed wire fences, while sufficient to discourage cattle, are passable by humans who can simply climb over the fence, or through the fence by stretching the gaps between the wires using non-barbed sections of the wire as hand holds. To prevent humans crossing, many prisons and other high-security installations construct fences with razor wire, a variant which instead of occasional barbs features near-continuous cutting surfaces sufficient to injure unprotected persons who climb on it. A commonly seen alternative is the placement of a few strands of barbed wire at the top of a chain link fence. The limited mobility of someone climbing a fence makes passing conventional barbed wire more difficult. On some chain link fences these strands are attached to a bracket tilted 45 degrees towards the intruder, further increasing the difficulty.

Barbed wire began to be widely used as an implement of war during World War I. Wire was placed either to impede or halt the passage of soldiers, or to channel them into narrow defile in which small arms, particularly machine guns, and indirect fire could be used with greater effect as they attempted to pass. Artillery bombardments on the Western Front became increasingly aimed at cutting the barbed wire that was a major component of trench warfare, particularly once new "wire-cutting" fuses were introduced midway through the war. As the war progressed the wire was used in shorter lengths that were easier to transport and more difficult to cut with artillery. Other inventions were also a result of the war, such as the screw-picket, which enabled construction of wire obstacles to be done at night in No Man's Land without the necessity of hammering stakes into the ground and drawing attention from the enemy.

During the Soviet-Afghan War, the accommodation of Afghan refugees into Pakistanmarker was controlled in Pakistan's largest province, Balochistan, under General Rahimuddin Khan, by making the refugees stay for controlled durations in barbed wire camps (see Controlling Soviet-Afghan War Refugees).

The frequent use of barbed wire on prison walls, around concentration camps, and the like, has made it symbolic of oppression and denial of freedom in general. For example, in Germanymarker the totality of the complex German Democratic Republicmarker border regime is commonly referred to with the short phrase "Mauer und Stacheldraht" (that is, "wall and barbed wire"). Recently Englandmarker and Francemarker have begun restricting the use of barbed wire due to the risk of injury it poses to trespassers.

Injuries caused by barbed wire

Movement against barbed wire can result in moderate to severe injuries to the skin and, depending on body area and barbed wire configuration, possibly to the underlying tissue. Humans can manage not to injure themselves excessively when dealing with barbed wire as long as they are cautious. Restriction of movement, appropriate clothing, and slowing movement when close to barbed wire aid in reducing injury.

Injuries caused by barbed wire are typically seen in horses, bats, or birds. Horses panic easily, and once caught in barbed wire, large patches of skin may be torn off. For this reason barbed wire was the single most important factor in rendering the U.S. Cavalry ineffective and led to the Cavalry's eventual dismantling. At best, such injuries may heal, but they may cause disability or death (particularly due to infection). Birds or bats may not be able to perceive thin strands of barbed wire and suffer injuries. For this reason horse fences may have rubber bands nailed parallel to the wires.More than 60 different species of wildlife have been reported in Australia as victims of entanglement on barbed wire fences, and the wildlife friendly fencing project is beginning to address this problem. The project is funded mainly by the World Wide Fund for Nature.Grazing animals with slow movements that will back off at the first notion of pain (e.g., sheep and cows) will not generally suffer the severe injuries often seen in other animals.

Barbed wire has been reported as a tool for human torture. It is also frequently used as a weapon in hardcore professional wrestling matches, most often as a covering for another type of weapon—Mick Foley was infamous for using a two-by-four wrapped in barbed wire—and infrequently as a covering of or substitute for the ring ropes.

Installation of barbed wire

The most important and most time-consuming part of a barbed wire fence is constructing the corner post and the bracing assembly. A barbed wire fence is under tremendous tension, often up to half a ton, and so the corner post's sole function is to resist the tension of the fence spans connected to it. The bracing keeps the corner post vertical and prevents slack from developing in the fence.

Brace posts are placed in-line about from the corner post. A horizontal compression brace connects the top of the two posts, and a diagonal wire connects the top of the brace post to the bottom of the corner post. This diagonal wire prevents the brace post from leaning, which in turn allows the horizontal brace to prevent the corner post from leaning into the brace post. A second set of brace posts (forming a double brace) is used whenever the barbed wire span exceeds . If an 8" post is * feet in length is driven four feet into the ground the brace post assembly can be omitted.

When the barbed wire span exceeds , a braced line assembly is added in-line. This has the function of a corner post and brace assembly but handles tension from opposite sides. It uses diagonal brace wire that connects the tops to the bottoms of all adjacent posts.

Line posts are installed along the span of the fence at intervals of . An interval of is most common. Heavy livestock and crowded pasture demands the smaller spacing. The sole function of a line post is not to take up slack but to keep the barbed wire strands spaced equally and off the ground.

Once these posts and bracing have been erected, the wire is wrapped around one corner post, held with a hitch (a timber hitch works well for this) often using a staple to hold the height and then reeled out along the span of the fence replacing the role every 400 m. It is then wrapped around the opposite corner post, pulled tightly with wire stretchers, and sometimes nailed with more fence staples, although this may make readjustment of tension or replacement of the wire more difficult. Then it is attached to all of the line posts with fencing staples driven in partially to allow stretching of the wire.

It is installed from the top down!

There are several ways to anchor the wire to a corner post:
  • Hand-knotting. The wire is wrapped around the corner post and knotted by hand. This is the most common method to attaching wire to a corner post. A timber hitch works well as it stays better with wire than with rope.
  • Crimp sleeves. The wire is wrapped around the corner post and bound to the incoming wire using metal sleeves which are crimped using lock cutters. This method should be avoided because while sleeves can work well on repairs in the middle of the fence where there is not enough wire for hand knotting, they tend to slip when under tension.
  • Wire vise. The wire is passed through a hole drilled into the corner post and is anchored on the far side.
  • Wire wrap. The wire is wrapped around the corner post and wrapped onto a special, gritted helical wire which also wraps around the incoming wire, with friction holding it in place.

Barbed wire for agriculture use is typically double-strand 12½-gauge, zinc-coated (galvanized) steel and comes in rolls of length. Barbed wire is usually placed on the inner (pasture) side of the posts. Where a fence runs between two pastures livestock could be with the wire on the outside or on both sides of the fence.

Galvanized wire is classified into three categories; Classes I, II, and III. Class I has the thinnest coating and the shortest life expectancy. A wire with Class I coating will start showing general rusting in 8 to 10 years, while the same wire with Class III coating will show rust in 15 to 20 years. Aluminum-coated wire is occasionally used, and yields a longer life.

Corner posts are in diameter or larger, and a minimum in length may consist of treated wood or from durable on-site trees such as osage orange, black locust, red cedar, or red mulberry, also railroad ties, telephone, and power poles are salvaged to be used as corner posts(poles and railroad ties were often treated with chemicals determined to be an environmental hazard and cannot be reused in some jurisdictions). In Canada spruce posts are sold for this purpose. Posts are driven at least and may be anchored in a concrete base square and deep. Brace posts are a minimum in diameter and are anchored in a concrete base square and deep. Iron posts, if used, are a minimum 2½ inch (64 mm) in diameter. Bracing wire is typically smooth 9-gauge. Line posts are set to a depth of about . The main advantage of steel posts is that they can be driven with a post moll or a cylindrical tube closed at one end with plate steel for weight, and pulled out by hand as opposed to wooden posts which must be pounded with a hydraulic pounder and often pulled with a front end loader. Conversely steel posts are not as stiff as wood and wires are fastened with slips along fixed teeth which means variations in driving height effect wire spacing.

During the First World War, screw pickets were used for the installation of wire obstacles; these were metal rods with eyelets for holding strands of wire, and a corkscrew-like end that could literally be screwed into the ground rather than hammered, so that wiring parties could work at night near enemy soldiers and not reveal their position by the sound of hammers.

See also


  1. Glidden Steel called its product "Barb Wire".
  2. "In my book a pioneer is a man who turned all the grass upside down, strung bob-wire over the dust that was left, poisoned the water, cut down the trees, killed the Indian who owned the land and called it progress." Timothy Egan is quoting a surprising source, the celebrated cowboy artist Charles Russell.
  3. Carlisle, Rodney (2004). Scientific American Inventions and Discoveries, p. 241. John Wiley & Songs, Inc., New Jersey. ISBN 0471244104.
  4. Henry D. and Francis T. McCallum,The Wire That Fenced The West(Norman: Oklahoma UP, 1965),p.29.
  5. Alan Krell,The Devil's Rope: A Cultural History of Barbed Wire(London: Reaktion Books Ltd, 2002), p.16.
  6. Ibid.,19.
  7. Reviel Netz,Barbed Wire: An Ecology of Modernity(Middletown:Wesleyan UP, 2004) p.10.
  8. Alan Krell,The Devil's Rope: A Cultural History of Barbed Wire(London: Reaktion Books Ltd, 2002), p.28.
  9. Henry D. and Francis T. McCallum,The Wire That Fenced the West(Norman: Oklahoma UP, 1965), p.27.
  10. Ibid.,29-32.
  11. Ibid.,41.
  12. Ibid.,87.
  13. Alan Krell,The Devil's Rope: A Cultural History of Barbed Wire(London: Reaktion Books Ltd, 2002), p.28.
  14. Joseph M., McFadden, "Monopoly in Barbed Wire: The Formation of the American Steel and Wire Company."The Business History Review,52,4,1978, p.2.
  15. Ibid.,5.
  16. Ibid.,10.
  17. Henry D. and Francis T. McCallum,The Wire That Fenced The West(Norman: Oklahoma UP, 1965), p.131.
  18. Ibid.,165-166.
  19. Reviel Netz,Barbed Wire: An Ecology of Modernity(Middletown:Wesleyan UP, 2004), p.108.
  20. Ibid., 124-127.
  21. Oliver Razac,Barbed Wire: A Political History(New York: The New Press, 2002), p.59.
  22. Ibid.,89.
  23. Ibid.,113.


  • Henry D. and Frances T. McCallum. The Wire that Fenced the West. Norman: University of Oklahoma Press, 1965. LoC: 65-11234.
  • Olivier Razac. Barbed Wire: A Political History, W. W. Norton & Company, 2003, ISBN 1-56584-812-8
  • Reviel Netz. Barbed wire. An ecology of modernity, Wesleyan University Press, 2004, ISBN 978-0-8195-6719-2
  • Biography of John W. Gates, barbed wire promoter who monopolized the industry with the American Steel and Wire Company, accessed March 29, 2006

External links


Patents – (about 570 were issued):
  • Patent history accessed September 21, 2006
  • – Lucien Smith, Kent, Ohiomarker, Wire fence – "rotary spools with projecting spurs" (June 1867)
  • – William Hunt, Scott, New Yorkmarker, Improvement in Fences – "sharpened spur wheels" (July 1867)
  • – Michael Kelly, New York Citymarker (!), Improvement in Fences – "thorny fence" (1868)
  • – Joshua Rappleye, Seneca County, New Yorkmarker, Improvement in Constructing Wire fence – tensioner for fence with palings (pickets) (1871)
  • – Henry Rose, DeKalb County, Illinoismarker, Improvement in Wire-fences – "strips provided with metal points" (1873)
  • – Isaac Ellwood, DeKalb, Illinoismarker Improvement in Barbed Fences – "single piece of metal with four points, attached to a flat rail" (February, 1874)
  • – Joseph Glidden, DeKalb, Illinois, Improvement in Wire-fences – twisted fence wires with short spur coiled around one of the strands (November, 1874) This became the most popular patent.
  • – Jacob Haish, DeKalb, Illinois, Improvement in Wire-fence Barbs – "single piece of wire bent into the form of the letter S" so that both strands are clasped (1875)
  • – John Nelson, Creston, Illinoismarker, Improvement in Wire-fence Barbs – barb installable on existing fence wire, (1876)

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