I got these in a box of mostly Tama drum parts. At first I figured something in the Granstar era. But they don't match up to anything I ran across. Granstars are round too. 6 sided - 5 mm wide on each side - approx 9 mm across - 17" tall - steel or nickel - 3 circumferential design cuts at the top - no knurling. Fairly hefty such that they don't seem cheap. One would think it's more costly to make this style vs. round ones. Never seen square/hex before.