The Primos A-Frame Diaphragm Turkey Call is simple, versatile and dependable. We love it when a call comes together. The A-Frame uses a patent pending process to trap the reeds and keep the perfect amount of tension, so the call will sound great over time. The A-Frame is contoured to fit your mouth. When you try an A-Frame, you’ll be amazed at how easy it is to use. Latex reeds.