Spare Part 2" Twin Wheel Rotate Caster Roller for Office Chair Product Name : Caster Wheel;Material : Plastic, Metal Fixing Stem Dia : 11mm/ 7/16";Wheel Diameter : 50mm/ 2" Wheel Length (not includeStem) : 56mm/ 2.2";Total Size (Approx.) : 80 x 67 x 54mm/ 3" x 2.6" x 2.2"(L*W*T) Color : Black;Weight : 80g Package Content : 1 x Caster Wheel