The Knight & Hale Glass Hammer friction turkey call features an internal soundboard and WIP (Wood Impregnated Plastic) technology for superior accuracy, durability and volume. The internal soundboard in the Glass Hammer friction turkey call is a system that features a soundboard within a soundboard. A new development in game calls, the internal soundboard enhances the Glass Hammer's accuracy by softening the turkey call's highest highs and lowest lows. It also enables greater volume and a more nasal sound, for added versatility and usability. The enhanced resonance will add a degree of realism to your turkey calling. The pot is made of wood-impregnated plastic. WIP technology provides you with the clear, crisp, rich sound of real wood. But, you also get the durability, water resistance and toughness of plastic. In addition, the surface of the call is waterproof glass. With the Knight & Hale Glass Hammer friction turkey call, you don't have to sacrifice anything.