Product Name : Caster Wheel;Material : Plastic, MetalFixing Stem Size : 1cm x 2.5cm/ 0.4 inch x 1 inch(D x H);Wheel Diameter : 5.1cm/ 2 inchTotal Size (Approx.) : 6.8 x 8cm(D x H);Color : BlackWeight : 160gFeatures a 360 degree swivel mounting plate attached to a double wheel roller system.Caster Wheel is perfect replacement compatible with your broken one on your office chair.Package Content : 2 x Caster WheelOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.