The i4 is designed to fit your head and stay that way

suitable for AEG version 2 gear box upgrades

Straight from the source of Airsoft itself

Disclaimer: Do not shine directly into human eyes

G&G CM16 ARP 556 CQB Carbine Airsoft AEG Rifle SpeedQB The i4 is designed toThe G&G Combat Machine ARP 556 CQB AEG Airsoft Gun is the bigger M4 magazine capable full metal brother of ARP9. This gun is designed to be an absolute CQB monster capable of maneuvering through those close quarters battle environments while keeping your profile small and being easy to point. This gun features an M LOK capable rail system with a sound amplifier on the muzzle to make sure your presence is heard across the battlefield. Modular rail