براغي ذات غطاء مقبس M16-2 × 60 مم | رأس مسطح، محرك سداسي | ملولبة بالكامل | فئة 12.9، سبيكة فولاذية، أكسيد أسود حراري (50 / عبوة)

The black oxide finish looks proper, and the hex socket drive gave me a clean, secure fit when I torqued them into my fixture plates. For a 12.9-grade screw, the thread engagement felt spot-on, no binding at all across all fifty pieces.

The black oxide finish on these bolts gives them a clean, professional look right out of the package, and they threaded into my fixture with no binding at all. For a Class 12.9 fastener at this price, the fit and finish are hard to beat.

Installed these in a jig for a heavy-duty press, and the 12.9 alloy steel held up perfectly under constant load—no stripping or deformation at all. The black oxide finish seems to resist oil and light moisture better than plain zinc I've used before.