براغي رأس مقبس سداسي 1/2-13 × 2-1/4 بوصة | محرك مقبس سداسي | رقعة نايلون | خيط جزئي | فولاذ سبيكي أكسيد أسود حراري (50/عبوة)

The nylon patch on these screws is a nice touch, they hold their position once torqued down without any extra thread locker. The black oxide finish looks clean and the hex socket drives easily with no stripping. Used them on a precision assembly and they seated perfectly.

Needed these for a custom jig I was building, and the nylon patch held tight even after multiple adjustments. The hex socket drive made installation in tight spots much easier than a regular hex head would have.

Installed a batch of these to rebuild a fixture for a milling machine, and the nylon patch on the threads really held them tight even under vibration. Black oxide coating makes them look clean and professional against the steel.