4pc Storage Rack Caster Wheels Adapts to Boltless Self Locking Shelving Racks

Installs on your existing storage rack. After installing these wheels your shelf can easily roll and no longer has to be stationary. These wheels adapt to storage racks that have boltless self locking shelving systems Wheel Material: PU Polyurethane. Locking wheels with ball bearings Includes 4 caster wheels and hardware 500 lb.