Features:* With excellent airflow design, you can easily whistle and make a loud, clear sound.* Lightweight, with key chain convenient to carry.* Double-hole design, great loud sound, for further spreading.* CNC machined, exquisite workmanship.* Through the polishing and etching process, which can effectively protect the post and is not easy to scratch and oxidize.* Apply to outdoor survival, self-defense, saving lives and collecting. Specific Cations:* Material: Aluminum Alloy* Size: Length 55mm × Width 15mm × Thickness 8mm* Weight: 14g Package Contents: 1pcs WhistleNote:1. The actual colors of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness.2. Please allow slight manual measurement deviation for the data.