M3-0.5 X 12mm 內六角圓柱頭螺絲 | 平頭內六角驅動 | 全牙 | 12.9級合金鋼熱處理黑氧化 (600/包)

The black oxide finish on these M3 screws gives them a nice, uniform look that's held up well in my jig builds. The 12.9 alloy steel feels seriously tough, and the hex socket drive takes torque without stripping.

I’ve been through a few boxes of these over the years, and the thermal black oxide finish is the first thing I notice—it’s uniform and doesn’t flake off when I’m torquing them down. The hex socket drive grips the Allen key snugly, no stripping on the 12mm length either. Class 12.9 alloy steel holds

Used a full pack to fasten aluminum jig plates and every single screw threaded smoothly without binding. The black oxide finish looks clean and seems durable enough for repeated adjustments. For the price, having 600 pieces of this grade is hard to beat for precision work.