M4-0.7 x 25mm ソケットキャップスクリュー | フラットヘッド 六角穴付き | 全ねじ | 12.9級 合金鋼 亜鉛メッキ (400 / パック)

Got these for a jig I’m building and the threading is clean all the way down, no binding even with a tight fit. The zinc coating looks uniform and they’ve held up fine under repeated wrenching. Class 12.9 gives me confidence they won’t strip on the tougher joints.

The flat heads sit perfectly flush in my mill's T-slots, and the hex drive makes tightening them a breeze. They held up well under heavy clamping pressure without any stripping.

I’ve been using these for a small jig I built, and the 25mm length was exactly what my setup needed. The zinc plating seems decent so far—no rust after a few weeks in my shop. They seat cleanly flush, which saved me from having to countersink further.