Kleinn Air Horns 130-1 XCR 2.0 Mini Triple Train Horn - Black Zinc Alloy Triple Air Horn Trumpets, 14-1/4-Inches, 11-1/2-Inches and 9-1/4-Inches Requires 150-PSI Onboard Air System (Not Included) All XCR 2.0 Black Coated Body with Black Zinc Alloy Trumpets Vortex 4  12-Volt Electronic Air Horn Solenoid Included Up to 152.9-Decibel Output