براغي رأس مقبس مقاس 1/2-12 × 6 بوصة | محرك مقبس سداسي | خيط جزئي | سبائك فولاذية أكسيد أسود حراري (25 / عبوة)

Used these to mount a heavy jig plate and the black oxide finish made them easy to identify versus my other fasteners. The partial threading gave plenty of grip without having to cut down a fully threaded bolt. Haven't had any issues with galling during tightening.

The threads cut cleanly into my fixture plate without any binding, and the hex socket drive seated the wrench perfectly for the full six inches. These are exactly what I needed for the jig assembly, and the thermal black oxide finish looks like it’ll hold up well on the shop floor.

The black oxide finish on these screws has held up perfectly during assembly, even with some accidental wrench scrapes. The hex socket drive gave me a solid bite without any cam-out issues, which made tightening them in a tight jig setup much easier than I expected.