The Diamondback DB15 features a 10" Chrome Moly Vanadium barrel with an A2 flash hider; pistol-length, Direct Impingement gas system; shot-peened, magnetic particle inspected Mil-Spec 8620 carrier; 9" M-LOK handguard; SB tactical SBA3 brace; Magpul MOE grip and aluminum receivers. Includes 30rd Magpul Gen3 PMAG. Firearm Specifications Manufacturer: Diamondback Model: DB15 Caliber: 300 Blackout Barrel Length: 10" Threaded Twist Rate: 1:9" Finish: OD Green Cerakote/Black Magazine Capacity: 30 Rounds