The entire bracket and internal parts are made of high quality steel, providing years of easy rolling and durability. [Soft rubber] This grip ring wheel material is made Made of high quality soft polyurethane, which has high mechanical strength, wear resistance, shock absorption and low noise. Good elastic PU rubber base also has extra dirt-repellent and self-cleaning action [Floor safety] Rolls smoothly and quietly on any hardwood, tile, wood, carpet, concrete floor without scratching, suitable for all types of floors. Low resistance, please pay attention to safety [Easy to install] Just take out the old caster and press in this popular stem caster, universally applicable to all kinds of seats. Specifications: The diameter of the wheel is about 2 inches