Airtech Studios G&G ARP9 / ARP556 BEU Battery Extension Unit Factory Replacement Parts (OEM) The rear sight is easy

The rear sight is easy to flip up and down

Output Energy: 1-3J Adjustable (build dependent)

A few BBs will naturally fall out when removing the magazine every time

The Gate NanoAAB Mosfet package will includes everything you will need to get started :

Airtech Studios G&G ARP9 / ARP556 BEU Battery Extension Unit Factory Replacement Parts (OEM) The rear sight is easyThe Airtech Studios G&G ARP9 ARP556 BEU Battery Extension Unit is designed to fit on G&G ARP series of AEG guns: fits on the ARP9 and ARP556. Very easy to install so you can add longer and bigger batteries in your rear stock buffer area. With it installed, you can use 9. 6v 1600mah nun chuck, and any longer 11. 1v batteries in it, with extra room to spare. This is a must have for those that want flexibility with battery space. For the ARP9 and ARP556,