براغي رأس مقبس M16-2 × 40 مم | رأس مسطحة بمقبس سداسي | خيط كامل | فولاذ سبائكي درجة 12.9 أكسيد حراري أسود (50 / عبوة)

The black oxide finish looks even better in person and held up perfectly when I torqued them into my tooling fixture. The hex socket drive seated cleanly with no stripping, and the 12.9 grade gives me confidence they won't fatigue under load.

I needed these for a jig I was building, and the thermal black oxide coating seems tough—no scratches after driving several in. The hex socket drove true without any cam-out, which I appreciated. Solid little fasteners.

The flat head sits flush perfectly on my jig fixture, and the black oxide finish resisted oil staining during a long machining run. These are exactly the strength I needed for heavy clamping loads.