M12-1.75 X 35mm براغي رأس أسطواني بمقبس سداسي | محرك سداسي | خيط كامل | فئة 12.9 فولاذ سبائكي أكسيد أسود حراري (100 / عبوة)

The black oxide finish on these screws held up perfectly during assembly, no flaking or chipping even with repeated hex key torque. They threaded smoothly into my jig fixture without binding, which was a relief after fighting with cheaper fasteners.

Installed a dozen of these into a steel jig plate and every single one seated perfectly without binding. The black oxide finish looks professional and held up well under clamping pressure.

Threads cut clean and the black oxide finish looks proper, no chips or burrs on any of the hundred I counted. Torqued them to spec on a fixture and the hex socket held up without stripping. Exactly what I needed for precision assemblies.