Friendly reminder: All items in our store are priced excluding tax. If you need an invoice, please contact customer service. Those who place orders silently will be deemed to have accepted the price as excluding tax.) The core of this whistle is made of aluminum alloy. The whistle is available in three color options (Blue, Black). This link defaults to silver. If you need other colors, please leave a message or contact customer service to make a note. Thank you! This product does not include a lanyard, the price is for the whistle only. If you need a whistle and lanyard set, please contact customer service! Product Name: High-Frequency Three-Tone Outdoor Survival Whistle Material: Aluminum alloy Weight: 18g Color: blue, silver, black Maximum volume: approximately 140dB Surface treatment: anodized, sandblasted whistle body Specifications: Length 56mm × Width 22mm × Thickness 8mm Usage scenarios: mountain climbing and camping, outdoor exploration, survival and rescue [Features] 1. Lightweight and equipped with a keychain, making it easy to carry; 2. Easy to blow, high decibel, three-hole sound production, loud and clear sound; 3. Made of aluminum alloy, it is tough and wear-resistant, with a surface finish achieved through anodization technology, which prevents fading and extends the service life.