Above is a raccoon in a Comstock single door 9x11x30 inch live cage trap with Comstock chimney adapter for raccoons.  Unlike other brands of chimney traps that “balance” on top of the chimney, this trap with adapter slides 18 inches into the chimney for much greater stability.  In this way it functions like the Comstock 29 inch raccoon chimney trap from the last post that slides all the way into a chimney out of view.  
Because this universal adapter works with 9×11 Comstock Cages, it can easily clipped onto a Comstock 30 or 36 single or double door cage to be used like the above photo that Matt Chittwood of Tennessee shared.  
There are now two options in Comstock Cages for trapping raccoons in chimneys, one as pictured above with the adapter and Comstock Cage or two, the Comstock Chimney trap that slips into a chimney out of view. 
This chimney cage adapter allows for Comstock 9×11 cages to be transformed into a raccoon chimney trap in little more than seconds for far less cost than other raccoon chimney traps that have but one use, while at the same time giving a trapper the advantage of being able to simply remove the adapter and return the cage to “regular duty” on the ground for skunks, woodchucks, armadillos etc.
  The advantage of the single purpose chimney trap is that it slides down the chimney out of sight and is only 29 inches long, very light in weight.      
Double Door Comstock Cage with Comstock Chimney
adapter in the upright position. 

Above is a Comstock Cage with chimney adapter
attached.  Looking “down the barrel.”
Comstock Chimney Adapter