Stainless post threaded 3/8"-16x3/4". For adding clamp directly atop tapped stem on some ballheads.
If you intend to install one of our quick-release clamps to the top of a ballhead that does not already offer any clamp, check first to see if the round platform atop that ballhead can be removed. Lots of ballheads, such as those offered by Linhof, have a round platform that simply unscrews, leaving behind a female, tapped socket in the stem of the ballhead. This socket is generally tapped 3/8-16, and allows you to mate the clamp directly to that stem, without the undesirable height increase that would accrue if the needless round platform was retained. Use Loctite type 272 (blue fluid) threadlocking liquid to make both connections semi-permanent. Buy Loctite #272 at your local auto parts store, or buy single-use applicator from Really Right Stuff (see panel at right).