Features: Double frequency, strong sound penetration, suitable for transmitting distress signals over long distances. Adopting a curved high-frequencies structure and equipped with anti loss clip. Light weight and durability, easy to carry. Outdoor adventurers, hiking enthusiasts, campers, and other outdoor activity participants. Suitable for outdoor survival, emergencies, communication, and safety assurances in outdoor activity. Specifications: Dimension:11.2x1.8cm/4.41×0.71in Component:Metal Package Includes: 1pc Emergencies whistled note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.