HOLO-KROME 640010280 #5-40 X 1/4" 內六角螺絲 | 圓頭六角驅動 | 合金鋼熱處理黑色氧化 (100顆/包)

Exactly the right thread fit for my jig setup, and the socket drive seats cleanly without stripping. The thermal black oxide coating held up fine through assembly, no flakes or residue. Good value for a hundred pieces.

The hex socket drive grips beautifully—no stripping even after a few tightenings. These little screws worked perfectly for a jig I'm building, and the black oxide finish adds a touch of durability. Exactly what I needed for precision work.

The black oxide finish on these #5-40 screws is really uniform and should resist rust well in my jigs. They threaded cleanly into the tapped holes without any binding, which was a relief.