1/2"-13 防鬆螺母 | 鋼 (500個/包)

Bought a full box of 500 for a framing project and the steel feels solid, threads are clean and catch on the bolt every time. The hex head lets me slip a wrench on without any wobble, which is exactly what you want when you're tightening in tight corners.

That hex-head shape made it dead simple to get a wrench on them in a tight spot, exactly what I needed for locking a stubborn bolt. The steel feels solid, and having 500 in the pack means I won't be running out anytime soon.

These things arrived in a sturdy box with all 500 accounted for, and the hex heads are cleanly machined without any burrs. They thread onto my bolts smoothly, which is exactly what you want when you need to lock something in place.