براغي رأس أسطوانية مسطحة M16-2 × 200 مم | محرك سداسي | ملولبة جزئيًا | فولاذ سبائكي درجة 12.9 أكسيد أسود حراري (10 / عبوة)

These bolts mated perfectly with my jig fixture's counterbores, the flat head sits flush without any wobble. The black oxide coating seems robust enough to resist light shop oils and chips during daily use.

The hex socket drive seated perfectly with my allen key, no stripping even under heavy torque on my jig setup. The black oxide finish gives them a clean, professional look that resists rust so far. Threads ran smooth the whole 200mm length, exactly as described.

I replaced a few bolts on my milling machine table with these, and the black oxide finish held up well against the cutting oil. The partial thread let me get a solid bite without bottoming out in the blind hole.