It actually just a improved cylinder but I cleaned the gun before my last hunt and it was a short hunt. Forgot to pull it out at end of season. Its stuck like no other. Tried all the tricks but rib is bent now so gotta get a new one. I even had one of my techs weld a bolt into the choke. But thanks for the info im going to try to get one asap. Im stressing out the season is coming soon!