Serpent Arms Custom Choke Tubes have been developed for our Patented "Rattler" cartridge to help create the most accurate and dense pattern at the intended ranges of the shooter. The chokes work by creating a quicker or slower separation between the cartridge and shot.
*Full Choke is dimensionally larger to allow shot to stay within cartridge longer in order to hold a tighter pattern at further distance. Ideal 20-40 yard pattern.
**Improved Cylinder Choke is dimensionally smaller to let shot separate from the cartridge sooner in order to create a larger pattern at closer distance. Ideal 5-20 yard pattern.
*** Each air shotgun comes standard with a Modified choke that holds an ideal pattern from 15-30 yards.
Choke Tubes
Improved Cylinder Choke will have 4 visible grooves around knurling of choke.
Modified Choke will have either 3 visible grooves around knurling of choke or NO grooves at all if it came stock on air shotgun.
Full Choke will have 1 visible groove around knurling of choke.
Reviews
I think you have the dimension definitions backwards.