HOLO-KROME 60106 3/8-16 X 1-3/4インチ ソケットキャップスクリュー | 皿穴六角穴付き | 合金鋼 熱処理黒色酸化仕上げ (50 / パック)

The fit on my milling fixture is spot on, and the flat head sits flush every time I torque it down. I’ve used a dozen so far on a jig build, and the black oxide hasn’t flaked or worn off even after repeated adjustments.

The thermal black oxide finish on these screws is exactly what I wanted for tooling—no glare, no slip, and they thread in cleanly every time. I've used a dozen so far on a jig build and not one came with a burred edge.

Used these for mounting a heavy-duty steel plate onto a milling machine jig, and the black oxide finish handled the oil and chips perfectly. The hex socket drive was a breeze with an Allen wrench, and all 50 screws were uniformly threaded.