This set of four 4-inch swivel plate casters sits between the smaller 2 and 3-inch options and the heavier-duty 5-inch casters, rated for 350 lbs per wheel and 1400 lbs combined. Dual ball bearings let a loaded cart or workbench roll with minimal effort, and the A/B brake locks both the wheel and the swivel action at once so the piece stops drifting once you've rolled it into place. The non-marking PVC tread protects finished floors while the reinforced steel bracket and thickened plate keep the casters from flexing under a fully loaded rack or machine base. Measuring 6.10 x 2.51 x 5.11 inches and weighing 7.95 lbs each, the casters mount with the included hardware kit, making them a practical upgrade for workbenches, tool carts, and storage furniture that need to move occasionally but stay put the rest of the time.