It will easily fit into your break open shotgun barrel and accept any 410GA ammunition up to 3" (three inches). After firing simply remove the adapter and tip upside down to remove the spent shell.  A smooth bore is gently bored through the adapter.  The 410GA cartridge side is precision CNC machined to the exact chamber dimensions to accept 410GA ammunition (SAAMI chamber specifications). 

Every adapter is laser engraved for easy caliber conversion identification.

Adapter orientation is not important and the adapter will  work in any position. 

Will fit any 20GA break open shotgun with 2 3/4" or 3" chambers.
Perfect for 'Preppers' or your Bug Out Bags.  Carry one gun and have the ability to shoot not only 20GA shells but also 410GA ammunition.
Surprisingly accurate.
Not recommended for pump action or semi-auto shotguns.  Designed for use with break open style shotguns only.