What do you call this type of spacer?

[cgallery]

I wish I had a picture. But there is a type of spacer I've seen in the past that uses two pieces that slide over a shaft. As one is turned in relation to the other, they expand or contract. Their mating surfaces are serrated so once you find the right thickness and tighten everything up, they no longer spin in relation to each other so they stay at that thickness. They often each have an arm so you can hold one steady and turn the other one.

I've search McMaster for "shim" and "spacer" but they don't seem to have them, or they're called something else.

Thanks!
Phil

[LJR]

You may be referring to a locking shaft collar or more likely a taper lock bushing. Try those and see if that gets you what you're after.