MAD's Patent Pending Hyper Growl makesthe next new step in deer call innovation byemulating the actual way that deer producesound. The addition of a "Hyper Ventilator"Tube to the air passage way creates themost realistic deer sounds ever recordedand a reed system that cannot be lockedup with as much air flow as you can give it.The integrated system even allows you toplace your hand over the end of the mainair flow and create perfect snort- wheezesthru hyper-Ventilator (Nostril) Tube withoutremoving air supply from the call.