The LMT MARS-L CQB 10.5″ 5.56 Quad Rail SBR is a short-barreled rifle chambered in 5.56 NATO that combines a compact profile with the modularity of Lewis Machine & Tool’s Monolithic Rail Platform (MRP). The one-piece aerospace-grade aluminum upper receiver features a 9.25-inch quad rail with continuous 1913 Picatinny rail sections for mounting optics, lights, lasers, and other accessories. Its 10.5-inch chrome-lined barrel utilizes LMT’s quick-change barrel system, allowing compatible barrel assemblies to be removed or installed using two locking bolts while maintaining the rigid monolithic receiver design.

The MARS-L forged ambidextrous lower receiver includes fully ambidextrous controls for the safety selector, magazine release, bolt catch, and bolt release, making the rifle adaptable for both right- and left-handed shooters. Additional features include an AXLE two-stage trigger, SOPMOD stock, G2 pistol grip, enhanced trigger guard, ambidextrous charging handle, and a standard M16-pattern full-auto bolt carrier group. The rifle ships with one magazine and an owner’s manual.

Specifications

• Caliber: 5.56 NATO
• Barrel Length: 10.5 in
• Barrel Construction: Chrome-Lined
• Barrel System: MRP Quick-Change Barrel
• Twist Rate: 1:7
• Gas System: Carbine-Length
• Operating System: Direct Impingement
• Finish: Black Anodized
• Upper Receiver: Monolithic Rail Platform (MRP) Quad Rail
• Rail Length: 9.25 in
• Rail Interface: Full-Length 1913 Picatinny Top Rail with Three Additional Picatinny Rail Sections
• Lower Receiver: MARS-L Forged Fully Ambidextrous
• Bolt Carrier Group: Standard Full-Auto M16 Pattern
• Trigger: AXLE Two-Stage
• Charging Handle: Ambidextrous
• Muzzle Device: A2 Birdcage Flash Hider
• Stock: LMT SOPMOD
• Grip: LMT G2 Pistol Grip
• Trigger Guard: Enhanced

Features

• Monolithic one-piece aluminum MRP upper receiver
• Quick-change barrel system compatible with LMT MRP barrel assemblies
• Compact 10.5-inch SBR configuration
• Fully ambidextrous lower receiver controls
• Continuous Picatinny quad rail for optics and accessories
• Chrome-lined barrel with low-profile gas block
• AXLE two-stage trigger
• Ambidextrous charging handle
• Includes one magazine and owner’s manual

At a glance