براغي رأس أسطوانية M42-4.5 X 320mm | محرك سداسي | خيط جزئي | فولاذ سبائكي فئة 12.9 أكسيد أسود حراري

The shoulder on these bolts is perfectly machined—no burrs or uneven threads whatsoever. Worked great for securing a heavy die in our press.

Needed a high-strength fastener for a jig I’m building, and the 12.9 alloy steel with that thermal black oxide looks solid and hasn’t shown any wear after a week of clamping. The hex socket drive seated perfectly with my Allen key, and the partial thread gave just the right grip for my application.

The black oxide finish on these screws handled a greasy machining setup without any marks or rust, and the hex drive seated perfectly in my torque wrench. I’m using them for a press fixture, and the 12.9 alloy steel gives real confidence in the hold.