Valken Tactical have their airsoft offerings on display during the IWA Outdoor Classics 2015. In this video taken from their booth, Josh talks about their AR-1 complete HPA-powered airsoft rifle which comes with its power source in the stock area. Also, for those who prefer doing their own HPA-powered airsoft gun projects, they have the V12 Engine Electro-Pneumatic Gearbox Kit for Version 2 gearboxes.