The Acme Thunderer 60.5 Brass is a well-known whistle that is used in sports, refereeing, and various signaling purposes. 

Key Features

• This whistle is a small, pea whistle typically made of brass metal giving it durability and a bright, piercing sound.
• It produces a loud and sharp sound, making it ideal for getting attention in noisy environments. The pea inside the whistle helps create a distinctive trilling effect.
• This whistle is commonly used by referees in sports like soccer, rugby, and field hockey. It is also used in emergency situations and by coaches, traffic police, and dog trainers.