G1 Features Include: 11 bps ( upgradable to 25+ with QEV and Board ) Customer adjustable 'left, right or center feed neck' 14"" Tactical Barrel M16 Style extending stock Hammer free Electro-pneumatic Design US (semi auto, fully auto and 3 shot burst) board options. US includes PSP and BillyBall modes as standard Simple 9-Volt Operation Multi-Gas Operation Light Microswitch Trigger with 2 Adjustable Points Simple Maintenance with bolt out back design Low Bolt Pressure Anti-Chop technology Max-Flo R Vertical Regulator Standard Smart Parts Barrel Thread Integrated Tactical Flashlight Mount 7 Accessory Rails for ultimate mounting options Built using high quality 6000 series aluminium and high grade composite materials for ultimate strength.