The M2.5 x 3.5mm Hardened Carbon Steel Screw is made from hardened carbon steel and is black in color. The thread type is an M2.5 and has a thread length of 3.5mm.
The M2.5 x 4.0mm Hardened Carbon Steel Screw is made from hardened carbon steel and is black in color. The thread type is an M2.5 and has a thread length of 4.0mm. These are a flat head design for flush mounting applications.