HOLO-KROME 61038 5/16-24 x 1-1/4" 內六角螺絲 | 平頭內六角驅動 | 合金鋼 熱處理黑色氧化 (100 / 包)

Just finished a jig for the shop and these flat heads seated perfectly flush every single time. The thermal black oxide finish looks sharp and the threads ran clean without any galling.

I needed some black oxide fasteners for a jig I was building, and these 5/16-24 socket cap screws fit perfectly. The hex socket drive grabbed onto my allen wrench securely without any slipping, and the finish looks professional.

I needed socket cap screws for a new jig build and the black oxide finish on these gives them a nice, consistent look. They threaded cleanly into the tapped holes without any binding, exactly what I was hoping for from alloy steel.