Triple Crown Coyote Calling Champion Les Johnson has teamed up with World Elk Calling Champion Rockie Jacobsen to create the best predator diaphragms in the industry. This diaphragm call is specifically designed to produce those low lonesome adult wolf howls. Quickly sound like the Big Dog with these easy to use diaphragms. The dome design ensures proper placement and superior control to lure them in.. Speak Wolf Predator Quest Style. Get To Howlin!!