The Rocky Mountain Hunting Calls 101 Raging Bull will bugle like a satellite bull challenging the herd bull. It also makes a great all-around call for cow/calf communication. The “Palate Plate” elk diaphragm call is designed to be placed further forward in your mouth, behind your front teeth, this helps to prevent gagging and gives you easier control of the latex. To operate the call, place the “Palate Plate” upwards to the roof of your mouth, latex down and open end of the diaphragm towards the front of your mouth.