S&W did call many types, which are for throwing, as grenades though they are merely smoke generating devices with a burning compound and CN or CS mixed in. Launcher fired tear gas devices are called "projectiles" by S&W, e.g., "No. 12 Tru-Flite Penetrating Projectile." This particular item predates my catalog by a decade and may have been discontinued by then. My only concern is the "instantaneous discharge." Those in this catalog are either "continuous discharge" or "blast dispersion." My concern is that they changed the terminology to blast dispersion to make it plain that there is a blast charge and yours is of that type. I don't know for sure.