The threaded rod on this clamp is a custom size (British Stand Whitworth 1/2-12) so if you don't have room for a large one ring nut or not, you need to order a special nut. The nut is a little cumbersome - not so easy to wind up manually when under the drill table and out of sight. I bought 2, one came with a washing machine the other didn't. 1 of the 2 ring nuts was not fully threaded so it will stiffen before it begins to tighten. Also, one of mine is slightly curved so the body of the clamp isn't really perpendicular to the table top of the drill press. The pressure plates are small and their surfaces are heavily serrated so that when the wood is clamped directly they leave a tooth pattern on the wood. I don't expect any issues and the clamps seem reasonably well constructed, but I'm a little annoyed that the stem isn't the standard 1/2-13 size.