The Spikes Tactical ST-9 is a 9mm AR-pattern rifle built on a dedicated blowback lower with Colt SMG magazine compatibility, offering a reliable 9mm carbine on familiar AR ergonomics. Type: Rifle Action: Semi-Automatic Caliber: 9mm Capacity: 33 Year introduced: 2015, USA Weight: 58 oz Overall length: 32" Status: Active Intended use: Home Defense, Competition