1、With great airflow design, it can easy to whistle and make a loud, clear sound 2、Double hole design, great loud sound, to spread further 3、Through the polishing and pickling process, which can effectively protect the post, and not easy to scratch and oxidation 4、Lightweight, with a keyring that is convenient to carry 5、Apply to outdoor survival, self-protection, life-saving and collect Descriptions: The is a aluminium alloy whistle, you can use it when you are in a extreme environment or in a state of emergency that you can use less effort to blow the whistle to call for help. Through the polishing and pickling process, which can effectively protect the post, and not easy to scratch and oxidation.This survival signal whistle, great for outdoor sporting events, camping, hiking, boating etc. Features: 1. With great airflow design, it can easy to whistle and make a loud, clear sound. 2. Lightweight, with a keyring that is convenient to carry. 3. Double hole design, great loud sound, to spread further. 4. CNC machined, exquisite workmanship. 5. Through the polishing and pickling process, which can effectively protect the post, and not easy to scratch and oxidation. 6. Apply to outdoor survival, self-protection, life-saving and collect. Specifications: Material: Aluminium Alloy Size: approx. 5.6 x 1.5 x 0.8cm / 2.2" x 0.59" x 0.31" Package Weight: approx. 11g Quantity: 1pc Package Included: 1 x whistle