Mobilize your workspace with this caster kit! Fits Nexel, Metro, Quantum and many other wire shelving manufacturers threaded studs. Featuring four casters, two with tread brakes. Each caster features a 4" Thermoplastic Rubber on Plastic wheel, plain bore bearings, and a dual ball swivel race for longevity and durability. This caster is perfect for use in kitchens, garages, offices, and storage areas. These casters are safe for use on all floors, including hardwood and tile. Make installation a breeze when you purchase our threaded stem caster wrench along with this kit.