12V Chrome Plated dual trumpet air horn is made of solid brass construction with non-corrosive Lexan polycarbonate diaphragmIncludes compressor, air tubing, fittings, and hardwareMaximum amp draw: 12 volt: 20 ampsdB(A) rating 121 at one meter, 1/3 octave band. Meets the ABYC and NMMA regulations for boats up to 20 meters/66 feet.Fundamental frequency 375/-15Hz, 315/-15HzDUAL TRUMPET AIR HORN has chrome plated brass construction throughout. Includes compressor, air tubing, horn button and mounting hardware. 12 volt. Size is 17 inch L x 7 inch W x 3-3/4 inch H. Chrome plated solid brass dB(A) rating: 121 at one meter, 1/3 octave band Includes compressor, air tubing, fittings, and hardware Non-corrosive LEXAN diaphragm Dimensions: 17 inches L x 7 inches W x 3-3/4 inches H Maximum amp draw 12 Volt: 20 Amps Fundamental frequency: 37515/31515