N623342-S2

This is an M6-1.0mm U-nut with a black phosphate finish that is used to hold the fenders to the radiator support, and maybe other places.  It has a reach of 19.5mm (25/32") from the middle of the screw hole to the bottom of the U, and handles panels from .34 to 4.0mm thick.  Fastenal has it as #0162877, and it is Auevco's #12575.