Defender Tactical Universal Minishell Adapter Kit for Mossberg Shotguns


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Defender Tactical Universal Minishell Adapter Kit for Mossberg Shotguns 

This kit essentially provides a conversion to 590S functionality, but in a more robust design.  It contains our patent-pending Universal Cartridge Adapter and low-drag no-snag Magazine Follower which allows smooth cycling of 1-3/4″ Minishells up to 3″ Magnum cartridges in the same magazine.  The adapter is constructed from vulcanized thermoplastic rubber, and the follower is machined from solid 6061-T6 billet aluminum.  This kit is compatible with any Mossberg 12-Gauge pump-action firearm with a 3″ Chamber and machined grooves in the receiver.  Please refer to the picture below or the installation video below to confirm your firearm’s compatibility.

Please note there may be a short break-in period for some adapters after installation.  Cycle a few magazines of full-size shells if you initially experience issues with 1-3/4″ shells, please reach out to us if problem persists.

*The Cartridge Adapter and Magazine Follower are optimized to function as a pair, but the factory follower may function as well for those that do not wish to remove it.


Rangeview Sports Canada
Licensed Gun Store in Newmarket, Ontario


Defender Tactical

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