Kleinn Air Horns 220 Black Dual Train Horn has 2 separate mounting trumpets 10.5-inches and 15.5-inches in length. Think fire truck or ambulance air horn but louder. The compact air horns can fit in almost any vehicle and deliver the big sound you need. Easy to fit, black finish and extreme truck horn sound; this air horn is the complete package. It requires an onboard air system up to 150-PSI for operation (not included). There are (2) Vortex 4 ?12-volt electronic air horn solenoid included. They feature black high-impact ABS material. Too Loud? Too Bad.