G&G BEU for G&G ARP/R2.0 Series (Battery Extension Unit) Pistons & Piston Heads The design has two nubs

The design has two nubs with a channel in between

Inner Barrel Length: 380mm

The new M40A5 makes the VSR-10 shy with the following new features:

It is perfect for shooters who love the ergonomics and aesthetics of the longer EPF2 but do not require the additional grip length or LiPo battery storage

An unique AEG designed by LCT's in house designers

G&G BEU for G&G ARP/R2.0 Series (Battery Extension Unit) Pistons & Piston Heads The design has two nubsThe BEU, or battery extension unit is a must for players who wish to add extra battery space to existing ARP series or Raider 2. 0 series AEGs. The unit provides an additional 50mm of battery space, developed by Airtech Studios.