DFX TECHNOLOGY AN-M8 Smoke Grenade A cylindrical grenade made of sheet metal of the same size, look and shape of the M7A1 CN and M18 signal grenades. Weighing 25.5 ounces the AN-M8 contains a filler of 19 ounces and employs an ignitor type fuse. After a time delay of 2 seconds it emits a dense white smoke for around 105-150 seconds. The grenade is used for signalling and screening type activities. The M8 is filled with hexachloroethane or HC for short, a chemical agent that produces a thick white smoke when burned and due to the high temperature of combustion, can also be used as an improvised incendiary device. HC smoke is toxic and can cause serious health problems with prolonged exposure.