براغي ذات رأس أسطواني | 7/16-20 X 5-1/2" | محرك سداسي | ملولبة جزئيًا | سبيكة فولاذ معالجة حرارياً بأكسيد أسود (25 / عبوة)

Installed these on a jig I’m building, and the partially threaded design grabbed perfectly in the thick steel plate—no slipping. The hex socket drive made tightening them down fast with a standard Allen key, and the black oxide finish should hold up well in my shop.

The black oxide finish on these screws looks sharp and held up fine during assembly of my jig, no chips or streaks. They threaded smoothly into my fixtures without needing much force, and the 5-1/2" length was spot on for what I needed.

The partially threaded design made installation in my machinery fixture much easier than with fully threaded screws. The black oxide finish seems durable, and the hex socket drove cleanly without stripping. These fit perfectly for my precision assembly needs.