Here's what other sites are saying:
The Coghlans Emergency Survival Horn is very loud! It operates with the simplicity of a mouth horn and blasts out audible sound up to 120dB. The membrane can be easily replaced with any thin flexible film. Comes with SOS printed on the body and a black break-away lanyard.
- Ramsey Outdoor
Alert rescuers to your location with the incredibly loud Coghlan's Emergency Survival horn. Simply blow into the small hole on the side of the horn to blast an audible sound up to 120 decibels-that's louder than your typical rock concert! Durable polypropylene body floats in water and has a bright orange color that's easily seen. SOS Morse code is printed on the side. Coghlan's Emergency Survival horn comes with a breakaway lanyard.
NRS Storm Whistle
Vargo Titanium Emergency Whistle
Harmony Fox 40 Whistle
Coghlan's Four Function Whistle
$3 - $4
NRS Fox 40 Safety Whistle
SOL Rescue Howler
Coghlan's Six Function Whistle
$10 - $12