The Raptors Airsoft RTQ Steel Enhanced Tight Bore Inner Barrel is a precision-machined upgrade component that can help improve the accuracy and performance of your airsoft gun. It is made from high-quality steel and features a square-cut design with a 6.02mm inner diameter that provides tighter groupings and improved accuracy. This inner barrel is compatible with CAR15/P90/G36C airsoft guns, and it can help increase your gun's velocity, range, and overall performance.