Slipstick CB682 2 Inch Replacement Office Chair Wheels (Set of 5 Casters) Universal Standard Size Stem 7/16 Inch x 7/8 Inch - Black Plastic Perfect office chair replacement set of caster wheels set of 5 Universal 7/16-Inch stem size works for almost every office chair Glides smoothly and quietly using standard 2" twin caster wheel design No tools required for installation 72-pound weight limit per wheel (standard set of 5 supports 363 pounds)