Every Phelps Signature AMP diaphragm is built to exact specifications and standards.
“This is the call I use whether I’m hunting or on the stage.” - Jason Phelps
"I have used other brands of elk calls, one in particular, that I used exclusively, and recommended. That all has changed, the first call of a Phelps diaphragm, fresh out of the package, and my eyebrows raised. I have been using diaphragms, since the mid 80's, there is a new leader, IMO. The only calls I will use, going forward, are Phelps. The feedback I've gotten from others I have recommended them to, is that it was money well spent!"