Premium Floor Safe Caster Wheels – Crafted with high-quality polyurethane soft plastic our rubber chair wheels are safe on hardwood flooring, carpets, tiles, and even hard rubber under chair office mats for scratch-resistant durability. Universal Steel Grip Stem – Compatible with most standard office chairs, excluding Ikea, these 7/16” x 7/8” size caster wheels are so soft on floors you won’t need an under office chair mat or other floor covering. Heavier Load Capacity – Able to support up to 270 lbs. per set our replacement caster wheels provide heavy-duty strength and resilience for long-lasting durability you can count on for home or office use.