M40A5 (T.Marui) 425mm x 6.03 Precision Inner Barrel

This is a polished inner barrel with 6.03mm inner diameter. The hop-up cutting is improved to minimize air-leakage around the hop-up set. The 425mm length is professionally made for best performance because it is able to fully utilize the gas from cylinder. All products are made for airsoft only.  They are not made for real steel firearms.