The OPSol Mini-Clip was designed to give "well seasoned" and "recoil sensitive" shooters the capability of shooting the trusty Mossberg 12ga platform without the usual recoil response.The Mini-Clip 2.0 Flex has the flexibility to accommodate a wider range of short shell lengths, should Aguila ever want to make an even shorter (or longer) Minishell. Re-loaders were very interested in this accommodation as are buyers of exotic products shorty shells in varying lengths. The 2.0 Flex will feed all but the longest in their line, the 3 buck. Features: Adapter allows use of Aguila 12 gauge 1-3/4 inches birdshot, buckshot, and slug Shells