براغي رأس مقبس M14-1.5 × 35 مم | محرك مقبس سداسي | كاملة الخيط | فئة 12.9 سبيكة فولاذ أكسيد أسود حراري (50/عبوة)

The black oxide finish looks properly done—no uneven patches and they thread in smoothly without galling. For jig work where I need consistent clamping force, the 12.9 hardness gives me real confidence these won’t strip or stretch under load.

Installing these on a precision assembly table and the threads ran smooth all the way down without binding. The black oxide finish gave them a nice, consistent look against the steel frame.

Needed these for a jig I was building, and the 12.9 grade gives me confidence they'll handle the torque without stripping. Fit perfectly into the tapped holes, and the black oxide coating is consistent across all 50 pieces.