براغي ذات رأس أسطواني 1/2-12 × 3 بوصة | محرك سداسي | ملولبة جزئيًا | فولاذ سبائكي مع أكسيد أسود حراري (50 / عبوة)

Installed these in a custom press fixture I'm building and the threads ran smooth all the way down without binding. The black oxide finish feels durable and didn't chip during tightening, which was a concern I had.

All six of my jigs came together exactly square because the black oxide finish lets the wrench seat in the socket without any slip. The partial thread gave me just the right grip for clamping a stack of plates, and the alloy steel held up to a full day of tightening without a hint of distortion.

The partial threading on these 1/2-12 socket cap screws made all the difference for my jig assembly, giving me just the right grip depth without bottoming out. The black oxide finish feels tough and uniform across all 50 pieces, and they seated perfectly with a hex key.