The Wolo 847 will give any 12-volt truck the powerful sound of a train air horn. The Siberian Express has been engineered with the latest technology using reinforced ABS. The sound produced by the three trumpets is incredible. Using reinforced ABS decreases the overall weight making installation easier and ensuring less vibration when driving on rough roads. The horns are operated by a heavy-duty 12-volt electric solenoid valve, included. 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” nylon high-pressure hose and a heavy-duty 12-volt electric solenoid valve. The Siberian Express requires an on-board air system (recommended Wolo on-board air system is Model 840).