M4-0.7 x 50mm 소켓 캡 나사 | 육각 소켓 드라이브 | 부분 스레드 | 12.9급 합금강 열처리 블랙 옥사이드 (400개/팩)

The black oxide finish on these M4 screws looks sharp and seems durable, no chipping after driving a dozen into steel. Perfect length for my precision fixture builds, and the hex socket holds the driver securely without stripping.

The black oxide finish on these has held up perfectly through a few weeks of shop use, no rust or wear. The hex sockets are cut clean, so my Allen key seats firmly every time without stripping. Exactly what I needed for a precision jig setup.

I needed some longer M4 fasteners for a jig project and these 50mm ones fit perfectly, the partially threaded design makes setup much easier than expected. The hex socket drive holds torque well without stripping, even in tighter spots with my T-handle key.