This version of the Discovery does not include a pump, tank, yoke or fill adapter. To connect your Discovery to a scuba tank, you'll need a scuba tank adapter with hose and a female quick-disconnect with male threads. The tank must have a K valve. To exhaust air or CO2 from the rifle, you need to purchase the degasser tool. Get into precharged guns at an unheard-of price and also get the accuracy of an expensive European rifle! Benjamin has bridged the gap and taken the pain out of PCP guns. Not only is this as low a price as you'll ever find on a PCP rifle, but it's so easy to pump up that a wispy teenager could do it! The Discovery has raised the bar for PCP guns because it uses only 2000 psi of air. While the European companies race toward higher and higher air pressures, Benjamin is going the opposite direction and making it easier than ever to use a hand pump. If you want to use a scuba tank or carbon fiber tank, you can do that, too, and get the benefit of many more fills than you would from a gun that operates with 3000 psi. The Discovery gives you a choice! The air reservoir is 135cc. The air tank has a male Foster fitting. The gun comes with a hardwood stock, Williams fiber optic front and rear sights, and a built-in air pressure gauge. When you open your box, you'll see easy-to-follow and easy-to-understand instructions that'll lead you step-by-step. If you're an experienced PCP user, you'll soon see that the Discovery is the easiest PCP you've ever used. If you're new to PCPs, you'll become a pro in just a few short steps. If you want to switch to CO2, that's easy to do, but you'll need a degasser tool to quickly exhaust all the air before filling with CO2. Attach the optional CO2 adapter, connect it to a standard paintball CO2 tank and fill 'er up! Now, commence to shootin'! With high-pressure air, you'll get up to 25 powerful shots before you need to pump up again. On CO2, you'll get a lot more shots per fill.