The Fox 40 Official NHL Caul Whistle with Fingergrip is a revolutionary pealess whistle named in honor of the late John McCauley. Built from an indestructible polycarbonate, it features a flexible fingergrip that fits a wide range of hand sizes while reducing impact energy on the hand. Its traditional low-tone trill cuts through arena noise, giving referees clear command of the game. A Cushioned Mouth Grip (CMG) adds comfort and tooth protection, and with no moving parts to freeze or jam, the Caul delivers flawless, reliable performance in any rink environment.