M5 X 5mm 杯頭內六角止付螺絲 | 316 不鏽鋼 (100 顆/包)

Just used these to lock a sprocket onto a motor shaft, and the 316 stainless is a relief—no rust worries even in my damp garage. The socket drive seated nicely with my hex key, and the cup point bit into the shaft exactly as intended. Solid little buggers for the price.

The cup point on these 316 stainless set screws bites nicely into the shaft without stripping, and the socket drive fits a standard hex key perfectly. I used a dozen to secure a pulley on a small machine and they haven't budged.

These replaced the zinc-plated ones I had been using on a pulley assembly, and the 316 stainless is a huge upgrade for outdoor gear. The cup point bites into the shaft firmly, so nothing has worked loose after a few weeks of vibration.