Power Calls Frequency Acrylic Canada Goose Call. The Frequency is a mid-sized short reed canada goose call designed to pack any punch the caller is looking for. Inspired by Kile Jones and paired with Power Calls Lightning Gut system worn in by Kelley Powers this call was made with every hunter in mind. The call's mid-sized frame is a hybrid between the Gravity and Wavelength allowing volume and speed, while maintaining a deep tone and easy-to-use back-pressure design. Structure: Machined CNC Acrylic Body Coloration: Stealth Black Core Guts: Polystyrene Worn-In Toneboard Reed: Mylar PreciseFit Reed Packaging: Hard Protective Case