Add the Tornado Impact grenade to your arsenal of Tornado Timer Grenades. The Impact grenade explodes on impact, compared to the Timer grenade that offers set back times of 1.5 or 3 seconds. The Impact Tornado explodes immediately once it hits a hard surface - even when dropped (from as little as one inch) onto concrete, but will hold - even with the pin pulled - when you shake it aggressively in your hand!