M14-2 X 220mm 內六角螺絲 | 六角驅動 | 半牙 | 12.9級合金鋼熱處理黑氧化物 (25個/包)

I needed these for a jig on my mill, and the 12.9 grade alloy steel handles the torque without deforming. The black oxide finish is holding up well under the shop lights, no rust yet after a month of use.

The partial threading on these 220mm screws gave me just the right grip for my jig setup, and the black oxide finish was uniform across all 25 pieces. They seated cleanly in the hex drive without any stripping, even at torque.

The 12.9 alloy steel feels rock solid, and the black oxide finish gives them a nice, uniform look that resists fingerprints. Threads cut cleanly into my precision assembly without any binding. These are the socket caps I'll grab again next time.