Built with a sturdy, copper manganese alloy coated with coated with nickel Compatible with Tokyo Marui and other compatible with other AEG Rifles/SMGs Durable, rigidly weighted barrels minimize vibrations and consistently improves accuracy Air Track Inner Bore design reduces air dispersion to maintain BB stability as it travels out of the barrel Hop-up bucking included In the Box 1X Inner Barrel 1 Nub 1X Bucking Specifications: Brand Poseidon Build Nickel Plated Copper Inner Barrel Diameter 6.05mm Inner Barrel Length 141mm Compatibility Tokyo Marui and Most AEGs California Proposition 65 Warning: Cancer and Reproductive Harm - www.P65Warnings.ca.gov