Office Chair Caster Wheels (Set of 5) - Heavy Duty & Safe for All Floors Including Hardwood - Perfect Replacement for Desk Floor Mat - Rollerblade Style w/Universal Fit Office Chair Caster Wheels (Set of 5) - Heavy Duty & Safe for All Floors Including Hardwood - Perfect Replacement for Desk Floor Mat - Rollerblade Style w/ Universal Fit UNIVERSAL FIT - 7/16" x 7/8" (11mm X 22mm) stem fits all standard office chairs SMOOTH GLIDING - Sleek, Modern, Comfortable. Polyurethane wheels protect your floors (scratch proof) SAFE FOR ALL FLOORS - Bamboo, Hardwood, Laminate, Linoleum, Pergo, Carpet, Tile, Concrete ULTRA DUTY 650 LB weight capacity. Premium Industrial Grade Casters & Performance Tested