1/2-20 x 3-1/4 英吋 內六角螺絲 | 圓頭內六角驅動 | 合金鋼 熱處理黑色氧化 (25 / 包)

The hex socket drive grabbed my 3/8" ratchet perfectly without any stripping—these bolts feel solid. Used them to reinforce a heavy-duty jig frame, and the black oxide coating held up well against minor scuffs during assembly. Exactly what I needed for precise tooling work.

The thermal black oxide finish looks sharp and held up perfectly when I torqued them into my tooling fixture. Hex socket drive seated cleanly with no stripping, and all 25 came with threads that ran smooth right out of the package.

I needed some quality fasteners for a jig I’m building, and the hex socket drive on these made installation with an Allen wrench really easy. The button head sits flush and looks clean, and the black oxide coating seems durable enough for shop use.