M16-2 x 50mm キャップスクリュー | 六角穴付き | 全ねじ | クラス12.9 合金鋼 熱処理黒色酸化被膜 (50 / パック)

Had to swap out the bolts on a jig I use daily, and these threaded in smooth right to the bottom with no binding. The 12.9 alloy steel feels noticeably tougher than the standard grade hardware I was using before.

The black oxide finish on these is flawless, and the 12.9 alloy steel gives them that reassuring heft when you’re torquing them into a jig. Threads cut clean and they seated perfectly in my fixture plates without any binding. These are going straight into my go-to drawer for future builds.

I needed some high-strength fasteners for a custom jig, and these Class 12.9 screws handled the torque beautifully. The black oxide finish looks professional and didn't flake off during tightening.