Rogue Studios show the V2 Optical MOSFET from Perun. Made for Version 2 AEG gearboxes, it can be programmed to certain firing modes as well switching active brake. It has precocking with the piston in rear position after each shot ready to fire the next BB. It also has a double shot mode in semi-auto stting that not only fires a round when you squeeze trigger but fires another round when released.