Purse your lips around the WAZOO and blow. That's all there is to the finished product!  But it's the story of design and development behind this little screamer that makes it a must-have for every kit and keychain.

There was not an existing whistle on the market that could live up to Wazoo's stringent requirements. They were too bulky, not loud enough, had parts that would fail, or were insanely expensive because they were made from Titanium. In a months-long experiment of compressible fluid dynamics, we tried every tube diameter, chamber length, hole opening angle, and cut depth.  Each variable was tied to the next and as a group, they controlled the pitch, volume, ease of use, and ability to "over-blow" and max out the whistle.  This SOS Micro Whistle™ is the culmination of all that research. It is balanced on the razor's edge of usability, functionality, and compact size. 

• Dimensions: 8.5mm diameter x 43mm long   (~0.33" x 1.7")
• All Aluminum construction (no plastic here!)
• Wide range of function - Starts resonance at low flow (good for kids) and can't be over-blown (good for adults)