XM177 Mini Electric Fully automatic airsoft mini machine gun. Fires 6mm Plastic BBs. Holds up to 75 rounds at a time. Fires 300 rounds per minute at 120-200 fps. This is a super durable gun made of ABS plastic. To load this gun you pull back a slide on the top of the gun. This gun is made by UHC so you know it is quality. To fire this gun in semi auto mode you must pull the trigger for just one second otherwise it will fire full auto. It will fire as long as you hold down the trigger.