M6-1 X 28mm 內六角平頭螺絲 | 平頭六角驅動 | 全螺紋 | 12.9級合金鋼熱處理黑色氧化物 (200顆/包)

The black oxide finish is holding up nicely against oil and chips in my shop. Every screw seated cleanly into my fixture plate without any binding. Exactly what I needed for a solid tooling build.

The black oxide finish on these held up nicely when I torqued them into my jig, and the hex socket drive seated the wrench perfectly every time. Class 12.9 strength gives me confidence they won't strip under load. I'll be ordering another box for my next project.

These M6 screws are exactly the right length for the jig I'm building, and the hex socket drive made installation much easier than a standard Allen key. The black oxide finish looks professional and seems durable.