M2-0.4 X 4mm ソケットキャップスクリュー | 六角ソケットドライブ | 全ねじ | クラス12.9合金鋼サーマルブラックオキサイド (600/パック)

I needed a hundred of these for a jig, and while the black oxide finish arrived with that dry, matte look I like, the 12.9 tensile rating gives me real confidence they won't strip under load. The 4mm length is perfect for those tight plate stacks, too.

I needed a solid batch of tiny screws for mounting a custom circuit board in a jig, and these M2-0.4 x 4mm cap screws fit perfectly with their hex socket drive, making them easy to tighten in tight spaces with a small Allen key. The fully threaded design and class 12.9 alloy steel give me confidence

Finally found M2 screws that actually feel machined, not stamped—the black oxide finish on these is uniform and doesn't flake off. They threaded perfectly into my 3D printer's linear rail mount without any binding. Exactly the precision I needed for jig assembly.