BEU Battery Extension Unit for ARP 9, ARP 556, CM16 Raider L 2.0 E, Red

The BEU (Battery Extension Unit) solves a common problem with compact AR platforms: fitting a usable battery into a stock that wasn't designed for one. On rifles like the ARP 9, ARP 556, and CM16 Raider L 2.0 E, the standard buffer tube leaves little room for anything beyond a small stick pack. The BEU replaces the stock grip with an extended polymer housing that accommodates larger battery configurations.

What it does. The extension creates additional internal volume for your power source without requiring a stock swap or stock modification. This means you can run larger battery configurations that would otherwise not fit. The unit is made from polymer, keeping weight down while maintaining durability under field conditions.

Compatibility. This BEU is designed specifically for G&G ARM platforms including the ARP 9, ARP 556, and CM16 Raider L 2.0 E. It interfaces with the existing receiver and stock mounting points, so no additional adapters or modifications are needed. The red colorway matches the corresponding variant of these rifles.

Before you buy. Battery and charger are not included. Measure your current battery to confirm it will fit the extended housing. If you are running a pack that already fits your rifle, you may not need this upgrade. The BEU is purely functional—it provides battery space, not additional features like integrated wiring or MOSFETs.