Crown Customs Barrel Extensions 3D-printed with PA6-CF20 carbon-fiber-reinforced nylo Lightweight, rigid, and heat resistant 14mm CCW (negative) threads on both ends Designed for strength without unnecessary weight Clean, low-profile extension for airsoft builds Available Lengths: 2″ 3″ 4″ 5″ 6″ Fitment & Length Notes: Compatible with standard 14mm CCW airsoft barrels and muzzle devices Sport Upper Receiver: 1″ of barrel length is built into the receiver Select an extension 1″ shorter than your desired final barrel length Example: Desired final barrel length: 6″ Sport upper → order 5″ extension Traditional Upper Receiver: 2″ of barrel length is built into the receiver Select an extension 2″ shorter than your desired final barrel length Example: Desired final barrel length: 6″ Traditional upper → order 4″ extension
