Trust me, they'll hear you. Easy-to-use Air Horn is a must for all marine applications. But unlike "canned" horns that are only good for a few decent blasts before sputtering out, this Horn from Shoreline Marine will NEVER "go flat."
That's because the air is supplied by you , instead of a sealed aerosol container. Just depress the plunger at the base, and let loose with an unmistakable "comin' through" that's impossible to miss. It's also easier on the environment!
Note: Pump Air Horn is very loud. Always aim away from yourself and others when operating, and use hearing protection when necessary. Colors may vary. Sorry, no choice.