Speak The Language of geese with the Shock Caller. The Shock Caller is a short-reed call, which reproduces all the sounds of Canada geese. This call is so easy-to-blow, you will be able to master it in no time. It enables you to call with minimal back pressure. To keep the call from sticking, due to moisture, Primos has crafted it with patented ditches on the sounding board. They'll be shocked it's a caller.