Full Choke
This is the tightest choke and therefore has the tightest shot patternWhat a shot group looks like when it is fired toward a sheet of paper.. It keeps the pellets together over a greater distance and is therefore used for longer shots, generally beyond 40 yards.

Modified Choke
This choke is not as tight as the full choke and is used for mid-range shots, usually between 30 and 40 yards.

Improved Cylinder Choke
This choke barely controls the spread of the shot and is used for shots between 20 to 30 yards.

Fixed Chokes

Unlike screw-in chokes, many shotguns also have fixed chokes
Fixed chokes are built in as part of the shotgun barrel and are not interchangeable. They can be found in the most common choke types: Full, Modified and Improved Cylinder.