You may want to look at this thread:
https://www.ar15.com/forums/Armory/MK9K-pics-and-info-request-/20-507233/
My custom Curtis Tactical can is shorter than the GSL Phoenix which is the MK9K reborn. I've owned 3 MK9K's and find this new can to be superior.
The new GSL Phoenix is also using aluminum baffles and tubes.
With the Curtis, there is no aluminum in the core for cleaning. All SS and the tube is Titanium. The Curtis Tactical can is actually lighter than the GSL eventhough the materials are heavier because it is shorter and the baffles are threaded together which eliminates the need for an inner tube.
I can't tell a difference in sound between it and my old MK9K's.
The GSL Phoenix, MK9K and my Curtis Tactical are all 2" in diameter. I had him make mine backward compatible with existing MK9K mounts. More discussed in the link above.
MK9K in the middle..I believe the Phoenix is the same length.