M4-0.7×16mm 圓柱頭螺絲 | 六角驅動 | 全螺紋 | 12.9級合金鋼 黃鋅 (400入/包)

For a full box of 400, the price works out great for our jig builds, and the Class 12.9 alloy takes a torx bit without stripping. The hex socket drive seated cleanly every time, which isn’t always the case with cheaper fasteners. Definitely my go-to for precision assemblies now.

Had to swap out some cheap bolts that kept stripping on my CNC fixture, and these Class 12.9 screws are way tougher—they torqued down clean and held firm without any deformity. The zinc yellow finish is a nice bonus for resisting a little shop grime.

Used these on a jig I’m building and the 12.9 alloy steel feels rock solid—no stripping even with repeated tightening. The zinc yellow finish hasn’t shown any rust after a few weeks in a damp garage. Pack of 400 means I’ve got plenty left for the next project.