هولو-كروم 32122 براغي تثبيت بنقطة كأس 1/4-20 × 5/8 بوصة | فولاذ سبائكي بأكسيد حراري أسود (100/عبوة)

The black oxide coating on these screws handled the oily environment in my gearbox without any rusting, a nice upgrade from plain steel. The hex drive seated firmly each time, making assembly much smoother than I expected. A solid set for securing brackets and clamps.

Used these to secure a pulley on a motor shaft and the cup point bit into the steel perfectly without slipping. The black oxide finish feels tough and hasn't chipped during installation. Exactly what I needed for a reliable mechanical lock.

The hex socket drive grabbed the cup point firmly when I set them on a shaft, no slipping at all. Thermal black oxide finish looks clean and should resist corrosion well. Handy having 100 in the pack for future jobs.