The Modify Hybrid Precision Inner Barrel is 509mm long with an inner diameter of 6.03mm, suitable for M16A1/ A2/ VN, AUG, M249. Made of high-grade stainless steel and aircraft aluminum alloy, the Airsoft Inner Barrel is extremely straight with high rigidity, which enables AEGs to achieve greater range and improved overall performance. Its O-Ring design reduces barrel vibration to improve accuracy. For optimal performance, always clean the airsoft inner barrel regularly.