براغي قبعة مقبس M4-0.7 × 35 مم | رأس زر محرك مقبس سداسي | ملولبة بالكامل | فئة 12.9 فولاذ سبائكي أسود حراري (400 / عبوة)

The black oxide finish gives them a nice, uniform look, and they threaded cleanly into my jig without any binding. For the price per piece, you're getting a solid pile of Class 12.9 hardware that's hard to beat for fixture work.

Used a handful of these in a CNC fixture, and the 12.9 grade alloy steel held up without snapping or stripping even under heavy torque. The black oxide finish also seems to resist chips and coolant better than expected for the price.

Put together a small jig for a production run and every single one of these M4 screws threaded smoothly without any burs. The black oxide finish looks great and seems durable too, and I appreciate having a whole 400-pack for future projects.