M30-3.5 X 60mm 육각 소켓 캡 나사 | 육각 소켓 드라이브 | 전체 나사산 | 12.9급 합금강 열처리 블랙 옥사이드 (4개/팩)

I needed fasteners that could handle the constant torque of my jig assembly, and these 12.9 alloy steel screws are holding up perfectly without any stripping. The thermal black oxide finish gives them a nice, uniform look too.

The hex socket drive seated my Allen key perfectly with zero wobble, and the 12.9 alloy steel feels rock-solid for a jig I threw together. For a four-pack at this size, the threading is clean all the way down and the black oxide finish looks sharp.

The black oxide finish on these screws handled the coolant mist from my milling machine without any rust, which surprised me. Installed them into a custom fixture plate, and the hex socket drive made torquing to spec much easier than a standard hex head.