It would appear that this call is very much like the M.A.D. version with the addition of a snort wheeze on the side........It looks like the same dual chamber style, and they even have a similar tube profile to create the back pressure.

I guess they didn't want to be left behind on the growl concept and lose loyal Primos customers who would have had to purchase a MAD call instead. I don't recall ever hearing the Priomos guys mention the term "growl" in any of their videos and I have all the new ones?