MS35338-47 | 軍規開口彈簧墊圈 | 鋼 (100個/包)

I’ve been using these steel lock washers on a shaky trailer hitch and haven’t had to retighten anything since. The split design grips the bolt threads firmly, even after a few bumpy miles.

Used a handful so far on a mounting bracket that sees constant vibration and they’ve held rock-solid, not a single loosened bolt since. The steel feels sturdy and the split design bites into the surfaces just as it should.

Finally, a pack that actually includes exactly 100 pieces as stated, and the steel feels robust enough to trust under heavy vibration. They slid onto my bolts without any binding and held firm during a test run on my lawn mower deck.