Features: 1.Every product has a unique Manufacturing Part Number label on the inner package that proves it has been qualified,which include Part Number,Model Number and inspection date information;2.If you have any questions about the item,please provide us the Manufacturing Part Number for checking,your profits will be guaranteed.3.Made of high-quality 45 steel, with long-lasting performance, sturdiness and durability, and long service life.4.Strong load-bearing capacity, each caster has a load capacity of 200 kg, it is not easy to be damaged, and the use effect is good.5.V-shaped wheels are suitable for triangles and have a wide range of applications. They can be used for industrial machines, trolleys, doors and windows.Specifications:Material: 45 SteelColor: YellowGroove Depth:8mm/0.31inchGroove Width:17mm/0.67inchWheel Diameter:31mm/1.22inchBracket Thickness:2mm/0.08inchInstallation Hole Diameter:6.2mm/0.24inchInstallation Pitch:42 x 18mm/1.65 x 0.71inchBracket Dimensions:56 x 31mm/2.20 x 1.22inchTotal Dimensions:56.2 x 44 x 40.4mm/2.21 x 1.73 x 1.59inch(L x W x H)Maximum Single Load: 200KGPer Wheel Load Capacity:441LbsWeight: 568gNote: When buying, pay attention that the load of 4 wheels can only be the sum of the load of 3 wheels, because when there is always an uneven road, the force of 4 cars cannot be even. Relaxing the load a little bit is conducive to prolonging the use time of the wheels.Package include:4 x Groove Rigid Wheel