براغي رأس أسطوانية 1/4-20 × 3-1/2" | محرك سداسي | صناعة أمريكية | فولاذ سبائكي مؤكسد أسود حراريًا (950/عبوة)

The black oxide finish on these screws held up perfectly during a recent machine build, showing no rust even in a humid shop. They threaded cleanly into every tapped hole without binding.

Needed some longer fasteners for a jig I was building, and these 3-1/2" screws fit the bill perfectly. The hex socket drive made installation simple with my Allen wrench, and the black oxide finish looks clean.

These black oxide screws are perfect for a recent machinery fixture I built. The threads were clean and started easily in tapped holes. For 950 pieces at this price, it's a solid value for tooling work.