Stebel Nautilus Compact Motorcycle Airhorn This is the loudest production motorcycle horn on the market. Here is the product description I lifted from Amazon.com: Product Description Want distracted drivers to pay attention? They will with this ear-splitting, 139 dB motorcycle air horn. Useful for getting that preoccupied driver to drop their cell phone, the piercing sound of this Stebel Air Horn can be heard three city blocks away! This motorcycle air horn produces a sound that is as much as 20 times louder than a stock motorcycle horn, so the Stebel Nautilus will help keep you safe. With a Big Truck high and low tone at the same time, the Stebel Nautilus eliminates the need for two horns. And, this loud air horn will last, as the horn can withstand more than 100,000 continuous action cycles. You'll be letting drivers know you're there for years to come. Read the Twisted Throttle review here: http://www.twistedthrottle.com/trade/productview/2137/ The horn is brand new, in box, 1000 baht. PM me if interested.