Storm All-Weather Safety Whistle - YELLOW<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Creates a clear， high frequency sound， with a power rating over 75% greater than other referee and safety whistles</li><li>an be heard under water， up to 50 feet</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51YZVph07sL.jpg" noproxy>