براغي رأس كروي 1-3/8-6 × 5 بوصة | محرك سداسي | خيط جزئي | فولاذ سبائكي أكسيد أسود حراري

Installed these in a jig I’m building, and the partial threading made alignment much easier. The black oxide seems durable so far, and the hex socket drive grabbed perfectly with my Allen wrench.

These screws are perfect for a jig I’m building — the hex socket drive engaged securely without any stripping. The black oxide finish looks durable and should resist rust well. Exactly the quality I needed for precision work.

The hex socket drive grabbed perfectly with my T-handle wrench, and the black oxide finish on these alloy steel screws resisted oil stains during assembly. They threaded smoothly into my jig without any binding, even at 5 inches long.