Which of the following is NOT a common shotgun choke?

In the context of shotguns, chokes are constrictions at the end of the shotgun barrel that control the spread of shot as it exits the barrel. Common choke types such as Cylinder, Modified, and Full help determine how tightly or widely the shot pattern will distribute over distance.

The Cylinder choke allows the shot to spread quickly with no constriction, making it effective for close-range shooting. The Modified choke provides a bit more constriction than the Cylinder, offering a balance between spread and range for medium distances. The Full choke provides the most constriction, allowing for a tight shot pattern suitable for longer shooting distances.

In contrast, "Double" is not a recognized or standard type of choke for shotguns. While "double" may refer to certain shotgun systems, it does not describe a shotgun choke type. Thus, "Double" is correctly identified as the option that is NOT a common shotgun choke.