House Of Gifts Whistle Referee-Coach Safety Alert Dog Rescue OutdoorWe presents football whistles which comes in different colors. Whistles are devices powered by air pressure to create a supersonic sound. They act as instruments to direct,prevent and supervise the action of the players during football matches and other gamesThe famous durable, whistle is the choice for pools and waterfronts. Its intense high-pitched trill can be heard over long distances. Water does not affect the performance.This whistles produces a lower-tone pitch. The distinct safety-sounding whistle is ideal for the elderly and children or wherever the need for a different sounding whistle exists.