The 556 version of the G&G ARP series, the G&G ARP556 PDW AEG is available at Gunfire and is featured in their "Instant Airsoft" series... "At first glance, the replica resembles yet another AR-15 replica, but aside from the implementation of gearbox V2 or the pistol grip, the similarities end there. We get a solid, compact PDW replica. In comparison to a similar replica - ARP 9 from Combat Machine series, ARP 556 was made almost entirely of metal. The replica features a foldable stock made of steel and polymer. The stock slide holds a connector for the battery (not included in the set) and a MOSFET unit. The replica features a custom pistol grip, trigger and a metal M-LOK® rail featuring license markings. The top of the replica features flip-up iron sights. Aside from the strong polymer, the replica also has steel elements, among others, a stock element, a shell ejection flap that is opened with the charging handle as well as screws and pins. The barrel of the replica has a custom muzzle device. The set includes a Hi-Cap magazine with a capacity of up to 450 BBs.

The GB aside from typical for G&G high-quality parts is equipped with an innovative ETU (Electronic Trigger Unit) system. The system supplements the role of the MOSFET circuit. Due to electronic operation, the system has gained a remarkable responsiveness to the trigger. Each pull results in a full operation cycle of the GB.

The ETU system has the ability to program fire modes. The User by default has the access to SAFE - SEMI - FULL AUTO - 3 round burst modes. The programming process is trivial - the User needs only to select the SEMI option and pull the trigger for 10 seconds. Once that is done, the third option of the fire mode selector will initiate the selected mode."