Features The wheels are made from white polypropylene which is wear resistant, shock damping and makes less noise. The bracket housings are made from iron plate with zinc plated on the surface for rust resistance. Swivel caster allows for movement in multiple directions, allow the caster to swivel 360 degrees under a load. Universal casters can be used for various purpose such as on desks, chairs, small trolleys, luggage cases, etc. Each caster has a max. load of 10kg, and the total load capacity is better to be less, for example, 30kg for 4 casters, in order to increase service life. Specifications:Material: Polypropylene, zinc-plated ironType: Swivel Wheel Diameter: 25mm / 1" Mounting Height: 35mm / 1.37"Wheel Thickness: 13mm / 0.51"Mounting Hole Diameter: 4mm / 0.15"Mounting Hole Pitch: 30 x 24mm / 1.18 x 0.94"Wheel Color: WhiteMax. Load: 10kg eachQuantity: 4 Package Includes:4 x Casters Package List