براغي HOlO-KROME 43030 5/16-24 X 1/2" بنقطة كوب ومقبس مسنن | فولاذ سبائكي معالجة حرارية بأكسيد أسود (100 / عبوة)

The knurled cup point gives a great grip for tightening into tight spots, and the black oxide finish seems durable. Worked perfectly for securing a small shaft in a test rig I built.

I needed set screws that wouldn't strip during installation, and these knurled cup points gripped the shaft perfectly without sliding around. Even better, the hex socket drove cleanly with no cam-out.

Finally found a set screw that actually holds tight on a shaft without stripping. The knurled cup point grips noticeably better than the smooth ones I've been using. These will definitely be my go-to from now on.