Hand Grenade No. 5, known as Mills’ Hand Grenade. Mills’ Hand Grenade No. 5 weighs about one and one-half pounds and is in constant and steady use at the front, being the best known of all grenades. It consists of an oval cast iron case, containing explosives and serrated to provide numerous missiles on detonation. In the center is a spring striking pin, kept back by a lever or handle, which, in its turn, is held in position by a safety pin.