If you're like me and hate laying on the floor with two open end wrenches trying to get a leg leveler to work then read on.
If you are building or have built a woodworkers bench and shims bug you then read on.
I'm doing A Real Cabinet Maker's Bench and definitely didn't want to shim the legs on my work of art. In Scott Landis's book on workbenches the Michael Fortune bench used leg levelers which could be adjusted with an allen wrench through a small hole in the top of the bench pedestals. He describes the benefit of this arrangement but didn't mention a name or a source.
So - after a lot of dead ends from a google search I found a source and the terms identifying this type of leg leveler (I'd been looking for glides, feet, bolts ...) What I found was a 3 inch diameter, 1/4 inch thick foot on a swivel connection to a 1/2" diameter threaded, ball ended, broach headed leg leveler and a T-nut for it.
From the top you see only a 5/8 inch diamter hole which I plan to hide with a domed plug -dry fit only. If you're making a nice heavy bench and would like to be able to get the top nice and level then check out (all one line)
Photos and dimensions, along with the supplier and part number are at the bottom half of the page. Not cheap but easy to use.
charlie b