HOLO-KROME 43020 براغي ضبط ذات رأس مقبس بنقطة كروية محززة 1/4-28 × 5/16 بوصة | فولاذ سبائكي مع أكسيد أسود حراري (100/عبوة)

Finally found a set screw that actually bites into the shaft without stripping—the knurled cup point grips way better than the smooth ones I've used before. These went into a tapped hole cleanly on my first try, and the hex socket fit my driver perfectly.

The black oxide finish looks clean and professional, and these screws hold firmly in tapped holes without slipping during tightening.

These knurled cup points really grab tight without stripping the socket, and the 5/16" length is perfect for my clamping setups. I’ve used them on a few shaft projects now, and they seat cleanly every time.