HOLO-KROME 730000200 #4-48 X 3/8" 內六角螺絲 | 內六角驅動 | 合金鋼 熱處理黑色氧化 (50 顆/包)

I was worried these tiny screws would strip when torquing into a jig, but the hex socket drive held perfectly without any cam-out. The black oxide finish is nice and uniform across all 50 pieces, and they fit exactly as expected.

For a #4 screw this tiny, the black oxide finish looks surprisingly uniform across all fifty pieces — no bare spots or flaking. Threads seated cleanly into the jig plate on the first try, which is exactly what I needed for precision work.

The black oxide finish on these #4-48 screws holds up well to repeated adjustments in my jig setup, and the hex socket makes them easy to drive in tight spots. They fit perfectly into my precision assembly work.