HOLO-KROME 72350 براغي مقبس 7/8-9 × 3-1/2" | محرك مقبس سداسي | فولاذ سبائك أكسيد أسود حراري (10 / عبوة)

The socket drive seated my hex wrench perfectly, no wobble or stripped corners. The thermal black oxide finish is holding up fine so far, and the threads cut cleanly into my steel jig plate.

The black oxide finish on these screws is holding up perfectly in my tooling fixture—no rust after a month of use. They threaded smoothly into the tapped holes with just a hex key.

Used a set of these for a heavy-duty jig I’m building, and the hex drive made installation much easier than I expected for such large bolts. The black oxide coating also seems to hold up well against chips and coolant.