M16 X 25mm 杯頭內六角止付螺絲 | 合金鋼 (50顆/包)

The cup point really bites into the shaft, so there’s no slipping even under heavy vibration. Took a bit of force to drive them in, but they’ve held rock-solid since.

I was worried about stripping the hex socket on smaller set screws, but the M16’s alloy steel handles high torque without a hitch. These cup points lock tight on my shaft collar without any slipping.

I needed a few for a heavy-duty jig I'm building, and the hex socket drive let me torque them down nicely in a cramped spot. The cup point really digs in, though I wish the package included a couple extras just in case.