Was ordered for a project that got cancelled. My inspection of these castors said I made a correct choice. These castors are designed for a heavy duty bench that requires levelling for usage. These castors have the levelling ratchet as part of the castor so you don't have to use any other tools. When you use these castors, you lower a foot to the floor and then raise the bench to the correct height. The bench will not move then. Nice for a run out bench for a table saw or a large work bench that requires moving and adjustment to match up to some equipment or other benches.