Rock River Arms have announced a new edition to their BT-9 Pistol range, a model with a short 4.5-inch barrel. The new 4.5-inch BT-9 pistol has an SB Tactical SBA3 adjustable stabilizing arm brace and feeds from GLOCK pattern magazines. It joins Rock River Arms’ other 7 and 10.5-inch barrel BT-9 pistol offerings which began shipping last April.

Here’s what Rock River Arms have to say about the 4.5in BT-9 pistol:

Rock River Arms, one of the industry’s most respected names in Modern Sporting Rifles and pistols, expands their series of semi-autos chambered in 9x19mm with the new BT92152. Designed to work with GLOCK® style magazines for optimal cross-compatibility with GLOCK® back-up carry pistols, the 4.5-inch BT-9 Pistol with SBA3 Arm Brace takes personal defense systems to new levels.

The 4.5-inch BT-9 is based on RRA’s billet aluminum lower receiver with a GLOCK® magazine-compatible flared magazine well. Integral to the lower receiver is a unique winter-style trigger guard that offers comfortable room for the trigger finger when wearing tactical or cold-weather gloves. The pistol includes RRA’s latest extruded aluminum upper receiver and comes standard with RRA’s 4.25-inch pistol length lightweight free-float M-LOK-compatible handguard.

Featuring a 4.5-inch chrome moly, 1:10 twist barrel with a Smith Vortex flash suppressor (1/2-36 threads), the BT92152 pistol incorporates the SB Tactical SBA3 pistol brace (with 5-position LOP adjustment) plus RRA’s overmolded A2 pistol grip and two-stage trigger for an ultra-compact and highly portable AR-platform 9mm pistol ideally suited as a home- or personal-defense firearm.

Rock River Arms new BT-9 series offers consumers the choice of four firearms consisting of three pistol configurations and one rifle configuration. Visit www.rockriverarms.com to learn more about the BT-9 series pistols and carbine.

*Specifications and parts subject to change

Here are the specs for the pistol:

• Caliber: 9mm
• Lower Receiver: BT-9 Billet Aluminum Lower with Glock Compatible Flared Magwell, Integral Winter Trigger Guard
• Upper Receiver: Extruded Aluminum A4
• Barrel: Chrome Lined 4.5-inch Chome Moly, 1:10 Twist
• Muzzle Device: Smith Vortex Flash Suppressor, 1/2-36 Thread
• Trigger: RRA Two-Stage Trigger
• Handguard: RRA Lightweight Aluminum Free Float, 4.25-inch Pistol Length, M-Lok Compatible
• Arm Brace: SB Tactical SBA3 Stabilizing Arm Brace, 5-Position Adjustable
• Pistol Grip: Hogue Rubber Grip
• Overall Length: 23.5 inches Extended
• Includes: One Glock Compatible Magazine, Manual and Warranty Info

Rock River Arms’ new 4.5-Inch BT-9 9mm Pistol has an MSRP $1,350.00. Find out more about Rock River Arms’ full range of BT-9 pistols over on their site.