Startech RKCASTER2 - 4-pack of universal M6 2-inch swivel casters for server racks, cabinets, 4-post racks. Replacement caster wheels or add mobility to a floor rack - Wheel Size: 2"x1.7" (50x43mm), Cold-Rolled Steel and Plastic, Included Hardware: 18x M6 Screws, 18x M6 Nuts, 18x Washers ( Set of 4) - Heavy duty casters support a stationary load up to 550 lbs (250 kg) or a rolling load of 165 lbs (75 kg) - Caster kit can be used on any rack with a 45mm x 75mm bolt pattern - StarTech.com Lifetime Warranty
