M30-3.5 X 100mm 소켓 캡 나사 | 육각 소켓 드라이브 | 풀 나사산 | 클래스 12.9 합금강 열처리 블랙 옥사이드 (5개/팩)

Installed these on a custom tooling fixture and the black oxide finish held up perfectly against metal shavings. The hex socket drive seated cleanly without any cam-out during torquing.

The threads cut cleanly when I torqued them into a jig plate, and the hex socket seated perfectly with no wobble. Fully threaded M30s this long are usually hard to find, so having five in one pack saved me a sourcing headache.

The black oxide finish looks properly done and evenly applied, which matters when you're using these in visible jigs. The 12.9 alloy steel feels dense and solid in hand, and the hex socket drive seated a wrench perfectly with zero slop.