Vktech&reg; 1/4inch Metal Train Truck Air Horn Electric Solenoid Valve Heavy Duty 12V Perfect for Air Horns & Air Ride Systems Power: 12V/24V Includes a 1/4" BARB fitting for 1/4" ID Hose Air Outlet: 1/4"NPT-MALE ,Air Inlet: 1/8" NPT FEMALE Max PSI: 180