2.Our Horn features an extremely powerful directly injected mini-compressor paired with a design to really charge and amp up the sound! All integrated into one small but powerful device! There is no bulky air compressor, a small device that produces incredible sound! Its so compact, almost HALF of our customers and install 2 horns for double the loudness!2 x Accessories1.Our 150DB Train Horn offers the loudest sound on the market, while also being the most compact Train Horn offered. The Train Horn is a high-quality, high-end train horn kit designed to integrate into as many trucks as possible. On top of that, the installation process takes less than an hour!Made from Quality metals and an ABS construction that wont oxidizeComplete Water and Weather Resistance3.While It's the perfect upgrade for trucks, our horn is also compatible with SUVs, passenger cars, boats and motorcycles. Like we mentioned earlier, The installation process takes less than an hour and is easy to do. Instructions and everything you need is included!Loud, Clear and Deep Train-Like SoundDiscrete, Compact1 x Speaker （compatible with SUVs, passenger cars, boats and motorcycles）Here's why the 150DB Train Horn is the BEST!150DB Sound Volume, The Most Powerful on The Market!