有頭螺絲，M6x12，內六角，自鎖

Used a handful of these M6x12 self-locking screws to secure a jig on my mill table, and they held the work piece rock solid even with some vibration. The hex key fits the socket head perfectly, so no stripping issues during installation.

The nylon patch on these M6x12 bolts keeps them locked tight even on my vibrating mill—no more retightening mid-job. Took about a minute to swap out the old screws with a hex key.

Fiddling with hex keys on these M6x12s is actually kind of satisfying, and that nylon patch really does its job—nothing has loosened on my bench setup even with vibration. Grabbed a handful for a quick jig, and the self-locking bite was instant. Solid little screws for the money.