The Storm® Whistle is the loudest whistle on the market today (75% louder than most other whistles), but is also the largest! This one is not for small survival kits, but if you need to be heard, this one is it. It is in use by the military, government and rescue organizations, and works above and below water. It has the same characteristics as the Windstorm® whistle above, only larger in design. It is in use by the US Army Special Forces and many other government and rescue organizations. Measures 3" long x 1-5/8" wide x 7/8" thick. Available in Orange & Black.