12 gauge to .22 LR Pathfinder Series | 12 gauge, Survival, Gauges
Short Lane Gun Adapters Stack-N-Pack Kit: Turning a 12 Gauge into a Truly Versatile Weapon
12ga to 38special adapter at 50 yards - YouTube
Eagle Gun Range -Macon GA - X-Caliber Ammo Adapter Set for Shotguns. It's an 8-piece set of drop-in adapters that measure seven inches long each, and it comes with a carrying case.