7 Round and 8 Round Remington Shotgun Magazine Tube Extension.

Increase capacity to 7 rounds (SMR0700) or 8 round (SMR0800) Made of virtually indestructible, matte black glass-filled nylon injection molded over a steel connecting nut. Will not rust or dent. New spring and instructions included. Minimum barrel length for 7 shot extension is 18-1/2" where as for the 8 round extension the minimum is a 20" barrel.

Pictured in the above image is the ATI SMC1100 Magazine/Flashlight clamp which is designed to stabilize the magazine tube extension as well as mounting a 1" tube flashlight to their tactical Shotguns.