This air option comes with a remote line adaptor and stock. You will need a remote line to attach your marker to an air tank. This configuration also allows you to use 60g refillable CO2 cylinders, 45g disposable cylinders and 12g disposable cylinders (with adaptor) as well. This butt stock has 5 adjustable positions. Shot capacity: To 1000+ shots (depending on air tank size use)