This replica model is actually a gas container. Instead of carrying your large ugly gas bottles out into the field, you can carry your gas in these replica flash bangs. These are in fact gas bottles themselves and will hold enough gas for about 7-8 full pistol charges. When your pistol needs recharging in the field, simply charge your pistol up with this dummy grenade gas bottle! Top pin section unscrews to reveal charge valve. You can fill this bottle itself through a valve on the bottom of the cylinder.