براغي رأس مقبس M20-2.5 × 180 مم | رأس مسطح محرك مقبس سداسي | ملولبة جزئياً | فئة 12.9 سبائك فولاذ معالجة حرارياً بأكسيد أسود (10/عبوة)

The threads on these M20 screws are cut clean and the partial threading makes alignment in my jig far easier than fully threaded bolts. The Class 12.9 alloy steel feels rock solid in hand, and the black oxide coating has a nice matte sheen that didn't chip during install.

The black oxide finish looks properly done, no uneven patches or rough edges on the threads. These 12.9-grade bolts torqued down smooth on my jig build and the hex socket seated perfectly without any wobble.

Installed these on a production fixture at work and the thickness of the thermal black oxide coating held up way better than the cheap zinc ones I used before. The hex socket drive seated perfectly without any cam-out.