This is an original replacement 6.03mm Inner Barrel (310mm) made specifically for the Amoeba Striker Spring Bolt Action Series. Amoeba Striker 6.03mm 310mm Inner Barrel - Short. This is the inner barrel to convert your long airsoft sniper rifle into a shorter CQB inner barrel length size. Inner barrel is the same drop-in fit as a 310 (approx) G-Spec VSR inner barrel. You can use the VSR parts cut for its hop-up. Heavy inner barrel 6.03mm diameter x 310mm long. OEM Amoeba product.