CEH Alloy Inner Barrel Upgrade 43cm x 9.5mm x 7.5mm - Universal. This is a standard alloy inner barrel, approx 7.5mm diameter. A simple, yet effective upgrade for your gel blaster. Alloy barrels assist to reduce friction, slightly increasing FPS and accuracy. Ideally suited for use with larger gel ball ammo, such as orange, clear or blue ammunition, though you may use all...