Premium materials and construction Replacement casters use high-quality polyurethane wheels and steel brackets for high strength, stable performance, safety, and durability. The smooth, hard-wearing surface resists wear and won’t scratch floors. Size and compatibility Stem: 11 x 20 mm; caster diameter: 2 in or 2.5 in. Available with or without brake. 360-degree rotating wheel. Maximum load: 120–140 kg. Smooth and quiet rolling 360° rotation with precision ball bearings provides easy, quiet chair movement and reduces the effort required to reposition the chair. Floor-safe performance Made of soft, durable polyurethane, safe on laminate, hardwood, carpet, tile, bamboo, and vinyl planks without leaving scratches or marks. Use scenarios - Replace worn casters on office or home chairs to improve mobility and protect floors. - Upgrade classroom, conference, or studio chairs for smoother movement with reduced noise. - Use on workbenches or computer chairs that require easy maneuverability and stable support.