Features: Tournament legal external velocity adjuster Removable grip frame for quick and easy upgrades Easily accepts expansion chambers, vertical and horizontal bottle adapters Works with CO2 or compressed air Stainless steel bottomline Impact resistant baked on coating Dual Picatinny mounting rails meet Military Standard 1913 Modular trigger system 1 year full parts and labor warranty through the manufacturer Slide-Away Feedport for easy cleaning and maintenance - offset for aim and accuracy Lightweight balanced construction Adjustable vertical front grip Selecta-Barrel adapter allows use of multiple barrel threads M-4 raised rear sight / carrying handle Collapsible CAR stock AR barrel system - Accepts A5 threaded barrels