This things a BEAST!!! The parts list :1 gears shimmed O ring nozzle Metal cylinder head Angle of engagement corrected with silicon pad Ball bearing piston head w/#14 O ring Light weight piston w/metal teeth G&G bucking & nub Rotary hop up chamber Ares 6.03mm tight bore barrel 100% cylinder to meet barrel length air volume requirements Zci hi torque neodymium magnet motor Quick spring change gear box, (unscrew the tube of the stock, in the cylinder unscrew the screw in there it reveals the quick spring change system watch ares YouTube videos to learn how to change the spring) To create the high speed effect it will need a sector chip, I didn't put it so it would feel like a dmr rather than a submachine gun. Asking 250 Venmo or PayPal only