ACME Thunderer Finger Whistle 477/660
 
Possibly the biggest selling whistle of all time, easy to blow, small, high pitch 117dBA and loud.
 
Favoured by customers in colder settings where metal might stick to the skin; also chosen by officials in sports, teaching, animal training, police authorities, military units and music specialists.
 
All plastic finger grip and legendary Model 660 Black Thunderer whistle.