1/2-20 × 1-3/4" 內六角螺絲 | 圓頭內六角驅動 | 全螺紋 | 合金鋼熱處理黑色氧化 (50個/包)

The black oxide finish on these is flawless—no drips or uneven spots, and they thread into my jig plate like butter. I’ve already used half the pack on a fixture build and every single one seated cleanly without binding. Solid pick if you need fully threaded 1/2-20s for tooling work.

Exactly the right thread for my milling machine's hold-down clamps, and the black oxide finish looks great while resisting chips. Each screw threaded smoothly with no binding, and that hex socket makes final tightening much easier than a standard bolt.

Used these on a jig for my milling table and they seated perfectly in the counterbore without any wobble. The thermal black oxide finish looks uniform and hasn't flaked off after tightening with an Allen key. Threads were clean from end to end, and all fifty arrived without a single burr.