M12-1.75 X 25mm 內六角螺絲 | 六角驅動 | 全螺紋 | 12.9級合金鋼熱處理黑氧化 (100顆/包)

The hex socket drive grips securely without stripping, which was my main worry for a jig build. These 12.9 alloy steel screws feel noticeably tougher than the 10.9 ones I used last time, and the black oxide finish hasn’t chipped during assembly.

The threads cut clean and the black oxide finish looks uniform across all 100 pieces, which I appreciate for a visible fixture. They seated snugly in my tooling plate without any binding, and the hex socket drive took the torque without stripping.

Finally found proper Class 12.9 hardware for my jig project, and these are exactly what I needed. The black oxide finish looks clean and seems durable, plus the hex socket drive made installation a breeze.