This call houses two metal reeds thus giving it the name double. The special reeds are designed to give this loud call a low-pitched and raspy sound unique to the predator calling world. You can use this call as the primary call or sometimes it works best to save it for later in the set to jar loose those educated critters. Works on all predators including coyotes, bobcats, fox, etc. Features: (2) metal reeds Loud, low-pitched and raspy Laminated barrel