Function: Compass (high accuracy, high definition, clear at a glance).Thermometer (to grasp the current temperature faster and more accurately).High decibel survival whistle (easy to carry).Display mode: pointer typeSports outdoor projects: bicycle cross-country hiking camping.Name: Professional Outdoor Multifunctional Lifeguard Whistle/Compass/North Pointermade in ChinaColor classification: green orangeCarrying method: hanging buttonNet weight: 16.1gPlease allow 1-3mm measuring deviation due to manual measurement.