I got this the other day, a 37mm DIP round case. Only marking

is what is on the case. I didn't know what it was, but some research identified it as a "Discriminating Irritant Projectile" a type of CS/Irritant round, was being trialled for Police use. A std grey aluminium case with what looks like a stainless steel adapter in the case, presumably for a blank propelling cartridge ? Any further information would be welcome.


