M24-3 X 190mm 內六角螺絲 | 內六角驅動 | 部分螺紋 | 12.9級合金鋼熱處理黑色氧化 (5個/包)

Used these to bolt down a heavy jig base that kept shifting in the shop—the partial threads gave plenty of grip without bottoming out. The 12.9 alloy feels seriously stiff, and the black oxide held up fine even with some oil on the threads. Solid set for the price.

The black oxide finish looks proper on these, not just cosmetic—should hold up well in my jigs. The 12.9 alloy steel feels dense and solid when torqued, and the partial threading gave me exactly the grip I needed for a tight assembly.

These machined perfectly into my tooling fixture threads, and the 12.9 alloy steel feels rock solid compared to the normal grade 8 stuff I've used before.