Description XUEMEI Whistle with Compass Function. Lightweight multipurpose whistle. Material: Mainly Plastic. With neck strap (50cm). Liquid filled compass increased the accuracy. High decibel survival whistle (loud whistle). Finger North (South) Needle (High Accuracy, Clear at a glance). Nylon hanging rope (more convenient to carry with you, rope length is about 40 cm (can be suspended on the neck). Excellent for camping, hiking and outdoor activities. Product description Features: 3PCS x Survival Whistle with Compass Function.Whistle with Compass Function. Lightweight multipurpose whistle. Specification: Material: PP + ABS Size: 6x2.7x1.9cm Color: Green Whistle code: Symbol description: Short tone (within one second); Long tone (more than 3 seconds) Communication (T): (one long tone) Used for team voice communication Set (U): (two short and one long) gather in the direction of the whistle Forward (V): (one short and one long) Send out during a break to represent the teams departure Waiting for the front team (W): (one short and two long) When the team travels too long, the front team is required to wait for the back team Request for support (S): (three short) Issued when you need help when you encounter difficulties Help (SOS): (three short, three long, three short) This is the internationally accepted SOS code Package Included: 3 x Compass Whistle Outdoor Camping Hiking Whistle