STOPBOX CHAMBER LOCK PRO

- 81 adjustable combinations - Security cable compatible - Improved grip Compatible with Mil-spec AR-15 Uppers. May have compatibility issues with some PSA Uppers. NOT COMPATIBLE WITH: Ruger AR-556 Radian A-DAC Upper Receiver Juggernaut Tactical AR-15 Billet Upper The Shotgun Chamber Lock is compatible with common pump 12 gauge shotguns such as the Mossberg 590 and Remington 870.