Wolo (847) Siberian Express Air Horn - 12 Volt Electric Solenoid Operated Will give any 12-volt truck the powerful sound of a train air horn Engineered with the latest technology using reinforced ABS The horns are operated by a heavy-duty 12-volt electric soleniod valve The trumpets are finished with an attractive semi-gloss black finish and the horns base is painted steel Horn comes with all mounting hardware and 10 feet of 1/4 inch nylon high-pressure hose and a heavy-duty 12-volt electric solenoid valve