WWII US FULLY INERT Ground Signal Rifle Grenade-This is the Model 18A1 and it is dated 1944. It says “Signal Ground White Star” on the round. This is followed by “Cluster M18A1”. "Signal Ground White Star" refers to an illumination flare used for signaling or battlefield illumination. “Cluster M18A1" refers to the Claymore anti-personnel mine, a directional fragmentation weapon. This measures approximately 9 ¾” tall. Aside from the actual charge, it is fully intact!