Cliff Keen Classic Fox 40 CK Logo Whistle WCK112 Description: Our most popular multi-sport whistle. The Fox 40 Classic is a pealess whistle with a sharp, clear sound. The Fox 40® Classic® is the standard choice referees and coaches at all levels, rescue professionals and general safety worldwide. Flawless, consistent and reliable Easy to blow and cannot be overblown Will be heard above ambient noise, loud crowds, the roar of engines, breaking waves and thundering gale-force winds Sound will be heard up to a mile away