This is the Coghlan&';s Four Function Whistle Essential Gear for Kids Camping Backpacking Features: Featuring a spring-loaded clip for attaching to a belt, bag or lanyard, this whistle also includes a AdegF and AdegC scale thermometer, magnifier, and compass. The high visibility yellow body makes it easy to keep track of. Featuring a spring-loaded clip for attaching to a belt, bag or lanyard, this whistle also includes a AdegF and AdegC scale thermometer, magnifier, and compass. The high visibility yellow body makes it easy to keep track of.