Bests & Worsts Reviews from Amazon

I liked the small size and construction of this whistle and it is loud as promised. However the resonator that makes it work is a little plastic insert in the mouth end of the whistle. If this plastic insert comes out the whistle will not work. I placed my new whistle in the freezer overnight (zero degrees Fahrenheit) and when I removed it the plastic insert easily slid out of the whistle. Since this is intended to be an emergency whistle that is unacceptable. I expect the metal and the plastic expand at different rates so if you put this in hot water the plastic would probably come out also, or maybe just melt.