M42-4.5 x 200mm 內六角螺絲 | 六角驅動 | 部分螺紋 | 12.9級合金鋼 熱處理黑色氧化物

The hex socket drive on these M42 cap screws made installation straightforward even in a tight spot, and the black oxide finish looks clean and professional. They bolted down a heavy press plate on my fixture with zero flex, exactly what I needed for a precision tooling setup.

I needed a heavy-duty fastener for a jig build, and the 200mm length with the partial thread gave me just the right grip depth. The hex drive seated firmly without any cam-out, even torquing them down.

The black oxide finish on these has held up perfectly under heavy clamping loads in my jig setup. The hex socket drive gives a solid, clean engagement every time I torque them down.