M20-2.5 X 45mm 內六角螺絲 | 六角驅動 | 全螺紋 | 12.9 級合金鋼 鍍鋅 (25 顆/包)

The hex socket drive seated perfectly on my wrench, and the 12.9 alloy steel feels rock solid under load. The zinc plating looks uniform, no flaking around the edges. These are my new go-to for precision jigs.

The threads cut cleanly into my jig fixture without any binding, and the zinc plating gives them a nice uniform finish that should resist shop grime for a while. For 12.9 grade at this price, they're a solid buy for heavy tooling work.

I was worried about stripping the hex drive on such large screws, but the 12.9 alloy steel feels rock solid even under high torque. The zinc plating has held up nicely against moisture around my jigs and fixtures.