Features: 3.U-shaped wheels are suitable for triangle irons. 4.Can be used for industrial machine tools, carts, doors and windows, etc.5.The item contains 4 pieces Track Roller Wheel made of Nylon and 45 steel, maximum single load up to 150KG.Please note that the load of 4 wheels can only be calculated as the sum of the load of 3 wheels, because when there is always an uneven road, the load on the 4 cars cannot be even. Relaxing the load a little bit is conducive to extending the use time of the wheels.Specifications:Material: Nylon & 45 steelColor: YellowBrand name: BQLZRSize: Total wheel height: 60 mm/2.36 inchWheel diameter: 2 inchWheel width: 27 mm/1.06 inchSupport thickness: 2.5 mm/0.098 inchBracket size: 68x40 mm/2.67x1.57 inchMounting hole distance: 54x24 mm/2.12x0.94 inchInstallation aperture: 6 mm/0.236 inchShaft thickness: 8 mm/0.314 inchGroove Width: 19 mm/0.748 inchGroove Depth: 11 mm/0.433 inchMaximum single load: 150KGWeight: 624 gPackage include:4 x Track Roller Wheel