براغي رأس أسطوانية M10-1.5 × 75 مم | محرك سداسي | ملولبة بالكامل | فولاذ سبائكي فئة 12.9 مؤكسد حراريًا أسود (50 / عبوة)

These bolts handled the torque specs on a production fixture I built without any stripping—the black oxide finish also held up well against oil and coolant splashes. I've used cheaper screws that snapped at the neck, but these 12.9 alloy steel ones are a solid upgrade.

Installed a batch of these in a custom jig and the black oxide finish held up perfectly under heavy clamping pressure. The hex drive seated cleanly without any stripping, and all 50 pieces had consistent threading.

Used a few of these to secure a metal bracket on a milling fixture, and the hex drive seated perfectly without stripping. The black oxide finish has held up well against some light coolant spray so far.