3/8-16 X 3-1/4" 內六角螺絲 | 平頭內六角驅動 | 部分螺紋 | 合金鋼熱處理黑氧化物 (50 / 包)

The flat head design on these 3/8-16 screws sits flush, which made mounting my tooling fixtures a breeze. The black oxide finish looks clean and feels durable.

Perfect for jig work where clearance is tight — the partially threaded shank gives just the right grip length. These screws have held up through several heavy-duty cycles without any stripping.

The flat head sits perfectly flush in my jig plate, and the black oxide finish looks clean and resists scuffs well. I've installed over thirty of these in a precision assembly setup and the hex socket drives true without stripping.