Patternmaster Black Cloud Choke is a full constriction choke (.690) that is compatible with the Black Cloud Ammunition or any ammunition with a "Flight Controlled" wad. It is also proven to shoot well with other brands of shotgun ammunition. This choke interchanges with Older Browning shotguns, Winchester 1300, Mossberg 500, and Weatherby, just to name a few. ***Disclaimer: Ammunition with a "Flight Control" wad may not pattern as well if shot through a ported barrel.