Includes 4 casters with brakes. Rotate 360 degrees. Smooth & Silent & Sturdy. The total locking brake locks both the wheel and the swivel simultaneously. 150 LB LOAD CAPACITY PER WHEEL. Each caster supports 150 lbs of load (with a 600 lbs. total capacity for all four wheels). All four of the casters have brakes while all four swivel 360-degree pivoting action for smooth wheeling on hard, smooth surfaces such as concrete with very low dragging. Double lock mechanism of both swivel and wheel rotation ensures stability. Plate Size: 2.75" (70mm) x 2" (50mm). Color: Black. Caster axle bolt size: 8mm(diameter) x 15mm(length). 2" Diameter PU Wheel. Polyurethane (PU) wheels offer the elasticity of rubber wheels combined with the toughness and durability of metal wheels. Safe for all floor types. Wide range of uses: commonly used in both industrial and residential applications such as workbenches, tool carts, tool chest, shopping carts, cabinets, bookshelves, coffee table and other movable furniture, etc... ,it is also perfect matching with vwindesk sit stand standing desk whose bolt needs to be as short as 15mm;