I like the concept of making it sound like a car horn. They are right that people will react better to a sound they understand. The price is too high and it's too big though.

> One of the big reasons people give for not commuting by bicycle is the fear that drivers won't notice them on the road.
They don't need this in the Netherlands and Denmark. They don't need helmets and high-visibility jackets, either. Why?
"Cycling in the US from a Dutch perspective" www.youtube.com/watch?v=m2THe_10dYs

I ride my bicycle more than my car. "See and be seen" is a crucial approach for drivers, cyclists and pedestrians. It blows me away how some people go about their travel. From carefree to distraction and even aggressiveness. In the city you get all kinds. If you're going to share the road with cars, your eyes have to constantly be on the move.
Car as well as bike riders can be obnoxious. Blasting a horn for little reason is very annoying. If I'm going to use my bike for any extended time on the street, I use a sports whistle, and even then sparingly or not at all. If you really want to be heard, a sports horn/blaster is cheaper (20 bucks), louder, lighter and even more obnoxious.
Yup. See and be seen comes first. Hear and be heard comes next. And keep your cool!

Can you provide a different sound - how about a nostalgic 'Aooga; Aooga'? Wish most cars have that instead of irritating HONK HONK.

Drive that bike on the sidewalk where it belongs, if bicycle want to use my road, they need to start paying taxes, should be around $175.00 US a year per a bike

I use a ball peen hammer to gain the attention of brain dead, nose picking drivers. And a rather loud VOICE. Amazing how brave some of these people are until they get out of the car to scream and yell and then suddenly realize they are completely WRONG. I used to ride my bike to my job as a cab driver. You'd be amazed at the entitlement mentality of both drivers and riders. Share the road people. BTW the horn above is completely unnecessary.

I'm an aggressive bike-rider, I haul-ass, abide by road signs, and take up the full-lane in slow (25 MPH) roads.
But even taking up the full lane, I've been cut-off 3 times by cars in the 10 times I've gone road cycling. (I'm usually on the trails).
I came from motorcycles... so I know the importance of a good horn. Any motorcyclist that insists on reeving their engine over laying on the horn is a fool.
Just like any cyclist who insist on yelling instead of laying on a horn is a fool. (granted, a horn isn't typically an option on a bicycle, so I've done my fair share of yelling).
That being said, I added this product to my cart immediately after seeing the video.

@Jay Finke, in every area of the U.S. that I'm aware of, adults are actually required to ride in the street (and in fact specifically PROHIBITED from the sidewalk), in the same direction as the flow of other vehicular traffic, and to obey all other regulations as well. "Share the road" isn't just a slogan, it's the law. Since many drivers (such as you) remain unaware of that, and even if aware are less than exemplary at applying it, a good horn is a good idea.
All that being said, 1.5 pounds and $50 seems ridiculous when as Oun Kwon noted, a sports horn is perfectly suited to the task...

Reminds me of that Fabulous Furry Freak Brothers cartoon where they sample the sound of an atomic bomb for their VW Beetle car horn...

@Jorel They ride in packs, or flat out think they own the road .when there are sidewalks 10ft across for them to ride on, in lots of areas. It's only a matter of time before one or two get run over by a texter. I'm sure getting run over by a car can't ever happen especially when it comes up from behind you, that gives you plenty of time to react, before getting crushed to death ( rolled up like a joint ) The total cost of bicyclist injury and death is over $4 billion per year. bicyclist injuries between 2001 and 2011: 8.9 percent. So maybe a licence or a IQ test should be implemented for all bicyclist.