ISO 7380 Button Head Socket Screws

Sizes M1.6 to M16, domed head about 0.55d tall. The low dome needs no counterbore, so it suits guards, covers, enclosures and any surface that has to stay snag-free, and the wide head spreads load on thin sheet better than a small cylindrical head does. What it does not give you is cap-head preload: the shallower socket limits tightening torque, and ISO 7380 marks these screws with a leading zero (010.9, 012.9) to show reduced loadability, commonly taken as about 80% of the same class in a cap screw.
Stock runs M1.6 to M16 in 10.9 (10B21 carbon steel), 12.9 (SCM435), A2-70 / 304 and A4-70 / 316, fully threaded, in plain, black oxide, nickel, black nickel and black electrophoretic finishes. Head height, hex key size and the exact difference from DIN 912 and DIN 7991 are compared side by side in the three-head socket screw comparison; counterbore and thread-length data for the cap head version are in the DIN 912 guide.