The totally new and awesome Tokyo Marui M870 Gas Airsoft Shotgun! A nearly full sized 870 style shotgun, with a unique gas system that's one of the best we've ever seen. Marui has knocked it out of the park as far as quality and craftsmanship is concerned. Full metal receiver and barrel, coupled with ABS plastic pump and stock furniture (like the real thing). The unique gas system holds its green gas (or original HFC134a) in the stock (via removable gas tank) and uses standard spring shotgun shells. The shells hold 30 BBs and shoots 3 BBs per pump/shot. It also has an adjustable switch, that allows you to shoot 6 BBs per pump/shot too! The shotgun can easily handle 'green gas', propane, but use with caution and use your silicone oil for lubricant. The original specs call for using HFC134a Japanese low-powered gas, but we've seen no problems with the more powerful gas. It depends on how often you shoot it and how you take care of it overall.The metal outer barrel contains three individual inner barrels to line up and fire each time you pull the trigger (3 or 6 per shot). This is a beastly airsoft shotgun and very rare. We have very limited stock, as Marui production is always limited, and this gun's popularity in Japan.