Item Type: Swivel Rubber Caster Wheels Material: Stainless Steel Wheel Material: Rubber Wheel Diameter: Approx. 50mm / 2.00in Installation Aperture: Approx. 6mm / 0.23in Distance from Hole Center to Hole Center: Approx. 35mm x 45mm / 1.38in x 1.77in Wheel Width: Approx. 21mm / 0.82in Board Size: Approx. 46mm x 58mm / 1.81in x 2.28in Quantity: 4Pcs Use Scenarios: Airports, Hotels, Warehouses, Trolleys Package List 4 x Swivel Caster 1Mute Rubber: The wheels are made of high quality mute rubber materials, which have high mechanical strength, shock absorption, wear resistance, and no damage to the floor. 2Stainless Steel Bracket: The bracket of this universal wheel is made of high quality stainless steel, which can prevent corrosion and rust. 3Double Ball Bearing: The accuracy double ball bearing with supporting steel sleeve is embedded to make the wheel rolling silently and smoothly. 4Application: Casters for equipment and furniture, including footstools, coffee tables, plant shelves, bookshelves, shoe cabinets, toy boxes, shopping carts, work tables, bed storage, etc. 5Flexible and Safe: Flexible and safe universal casters make possible to rotate with the equipment, which is conducive to transportation.