Feb 13, 2022 · The HDX 4 in. Industrial Casters are designed to hold up to 150 lbs. each, fitting units with 1 in. Dia. posts and 3/8 in. inserts. Featuring a swivel design for easy mobility, the pack of 4 Perfect Steerable Transfer Cartludes brakes on 2 of the wheels for control and safety. Supporting up to 600 lbs. for a variety of tasks, the casters are designed for use on HDX light- and heavy-duty 4-shelf, 5-shelf and 6-shelf units.