Hunter's Specialties HS Strut Hammerin' Crow Call features a realistic sound and a simplicity that make it the choice of National Champions and weekend hunters alike. It's designed to call with less air than conventional calls, so it takes less effort to use. Blowing lightly is all that's necessary. Crows have vocabularies of about 25 words, but 3 of those sounds are sure-fire ways to get gobblers to answer and come running. The back of the package has complete instructions to produce the "assembly call", the "alert call", and the "caw".