MPC Train Air Horn Kit; Three Separate Huge Trumpets, 12-Volt 150 PSI Compressor Separate Mounting Chrome Triple Train Horns (17", 15", 13" lengths) w/ 12v electronic solenoid included. [Air System] 150 PSI 12 Volt Sealed Air Compressor (Dimensions: 6.5" x 3.5" x 4.5") and 1 Gallon Air Tank (Dimensions: 10.75" x 5.75" x 8") Kit includes a pressure switch (120 PSI on/150 PSI off), 12 ft of 1/4" air line, push button switch, all necessary tank fittings and mounting hardware Free Wiring Kit!