مسامير رأس مقبس HOLO-KROME 720001497 5/16-18 X 5" | محرك مقبس سداسي | فولاد سبائكي أكسيد أسود حراري (5 / عبوة)

The black oxide coating held up perfectly when I used these for a jig I was building in my shop. The hex socket drive made installation much easier than using a standard wrench on a 5-inch bolt.

Installed these in a machine guard that sees daily vibration, and so far none have loosened—the hex drive makes torquing them down clean and easy. Exactly the length I needed for a thick jig assembly I’m building, and the black oxide coating seems like it’ll hold up well against workshop grime.

The black oxide finish on these screws looks clean and professional, and the socket drive engaged my hex wrench without any slipping. They've held up well in my shop jig through several test runs, and the 5-inch length gave me just enough bite for the assembly.