The center or Interior. The Branta Canadensis Interior is commonly known as the interior Canada Goose, and that is exactly what this call is designed to sound like. The CORE comes standard with our RAID guts system which allows you to mimic those Interior Canada Geese. With this being said, this call will be a little higher pitched than the life sentence. The CORE is fun to blow, has a ton of range, lots of back pressure, and a good crack on the top end with a really good low end because of the RAID guts system.