MPC 2-Trumpet Train Air Horn Kit for Trucks: Complete 12v System Includes All You Need For Maximum dB Oversized Dual Chrome Train Horns (15" & 13" Trumpet Length) w/ 12v Solenoid All-in-one Air System w/ 130 PSI Compressor & 5 Liter Air Tank (Dimensions: 24" L x 5.25" W x 6.75" H) Kit includes a pressure switch (100 PSI on/130 PSI off), 12 ft of 1/4" air line, push button switch, all necessary tank fittings and mounting hardware Free Wiring Kit!