Magpul - BSL Arm Brace for AR Pistols (Mil-Spec)

Magpul BSL Arm Brace – Mil-Spec is purpose-built to enhance the single-handed employment of AR15 and M4 large-format pistols. Designed with Magpul’s trusted engineering and aesthetics, the BSL provides improved control, durability, and sling integration for shooters who demand more stability from their pistol platforms.

Compatible with Mil-Spec carbine receiver extensions, the BSL features a simple, rugged, and tool-less adjustment mechanism for easy one-handed use. Its high-strength polymer and metal construction ensure reliable performance, while the integrated ambidextrous rear QD cup and dual M-LOK® slots give shooters versatile sling mounting options. By allowing stabilizing sling tension, the BSL greatly increases control during one-handed firing.

• Platform: AR15, M4
• Compatibility: Mil-Spec carbine receiver extensions (not compatible with proprietary, pistol, or commercial-spec tubes)
• Tool-less Adjustment: Simple, single-handed deployment and collapse
• Sling Options: Ambidextrous QD sling cup and two M-LOK slots for added configurations
• Durable Construction: Proprietary Magpul polymer reinforced with metal
• Made in the USA: Designed and built to Magpul’s high standards

Legal Disclaimer: The BSL Arm Brace is designed and intended only as a forearm stabilizing accessory for lawful one-handed pistol use. It is not a stock and is not intended to be fired from the shoulder. Any redesign or misuse may render the firearm NFA controlled. All ATF, NFA, state, and local regulations apply. The user is responsible for compliance with all applicable laws.