Jeff The KID talks about the Aluminium Alloy Barrel made for the Action Army AAP-01. The machine translation is problematic so try to make sense out of it to understand more... "The long-awaited AAP-01 aluminum alloy barrel is open for pre-orders. The position is exactly the same as AAP-01. There is an O-ring in the flasher cap to prevent the flasher cap from loosening due to the action of the gun. The weight of the gun is better. The color is gold, silver and matt black.