The Zink Thunder Series calls consists of four aluminum-framed mouth calls. This one is the Zink Thunder ST Diaphragm Call. It is a 3-reed construction with a snake tongue design. This mouth call creates rasps with a high-pitched front end, as well as yelps, purrs and clucks.FeaturesCustom stretched and handmade in USA3-reed constructionSnake tongue design rolls easily and requires little air