POWERHOUSE is a roof mount air horn, that has dual metal chrome trumpets. Features Wolo's new heavy-duty air horn compressor. POWERHOUSE produces an extra loud alerting sound, ideal for the vehicle owner that demands to be heard! Included in kit is chrome weather protector covers for both trumpets, to ensure years of dependable service. The Wolo 418 truck horn is a perfect addition for any 12-volt truck, 4X4, RV or SUV. So if you want the sound of a big truck, without an on-board air system, then POWERHOUSE is the horn for your vehicle. It will sound as good as it looks on your vehicle�s roof. The kit includes a heavy-duty compressor, 30-amp relay, hose, weather protection covers and mounting hardware. Instruction in English / Spanish.