براغي رأس كوبية سداسية 5/8-18 × 1/2 بوصة | فولاذ سبائكي (50/عبوة)

The cup point bites into the shaft way better than the flat-tip screws I've used before, so these stay put under vibration. They're alloy steel and threaded cleanly right out of the package, every one of the 50 seated without a single burr. Definitely my go-to for locking down collars in tight spots

I was worried about the cup point stripping under torque, but these alloy steel screws bit in perfectly and held fast. The hex socket drive gave me all the leverage I needed in a tight spot.

Used a couple of these on a machinery adjustment, and the hex socket drive made torquing them down in a tight spot so much easier. The alloy steel feels plenty durable for the job.