Office Chair Open Disk Extra Large Carpet Casters 3"- Heavy Duty 5 Pack Universal Office Chair Open Disk Casters for Carpet Floors 3"- Heavy Duty Package of 5 175 pounds weight capacity each caster (875 pounds total) Will work on virtually any office chair with a metal stem on the caster of 7/16" wide x 7/8" long Designed for thicker carpets- even if you are not using a floor mat! The larger diameter twin wheels allow casters to carry more weight. Roll smoother and last longer