Hadley is the worldwide leader in air horn systems. You’ll see our horns used as original equipment on over-the-road, tractor/trailer rigs. And, when combined with a Hadley Air Compressor, they’re the number one horn used on SUVs, 4 x 4’s, vans, pickup trucks, motor homes, motorcycles, and power / sail boats. The extensive Hadley product line offers Round or Rectangular Bell Horns in single or dual projector configurations as well as a variety of finishes including matte black, chrome ... An air compressor horn generates a much louder sound. These horns can reach up to 153 decibels. Some of them are able to sound out at up to 157 decibels depending on the variety of horn and the size of valves and air systems. These train horns for trucks will be loud. What Sound Should it Make? Most people are of the belief that more horns mean a more powerful sound, but that’s not accurate. There is no bulky air compressor, only a small device that produces incredible sound! Its so compact, almost HALF of our customers buy and install 2 horns for double the loudness! Train Horn is Suitable For Almost Any Vehicle! While It's the perfect upgrade for trucks, our horn is also compatible with SUVs, passenger cars, boats and motorcycles.