براغي رأس كبس 1-1/4-7 × 5 بوصة | محرك سداسي مسطح الرأس | ملولبة جزئيًا | فولاذ سبائكي أسود حراري

The black oxide finish held up perfectly during assembly, even with some heavy torque applied. These flat head screws seated flush without any wobble, which was crucial for my jig setup.

Installed a batch of these into a steel jig plate yesterday and the black oxide finish wiped clean without any residue. The partially threaded length gave me good grip for a 5-inch fastener, and the hex socket seated deep enough that I didn't strip a single one.

The hex socket drive on these screws grips the Allen key perfectly, making them easy to install in tight spots on my fixture table. The thermal black oxide finish looks professional and hasn't shown any wear after repeated use.