This dual trumpet electric horn is 100% stainless steel housing, 304 non-magnetic grade with a bright polished finish that will not rust. Designed for exterior use and ideal for boats in a salt water environment and also RV's, SUV's & Trucks. Will sound at a loud 125db. Ideal for any 12-volt system vehicle in almost any weather condition. This horn is maintenance free and does not require a compressor or hoses. Simple 2 wire connection (positive & negative) for quick installation. Horn trumpets dimensions: 13-1/2" and 15-1/2" long. *IMPORTANT* While horn is out of environment, MUST perform inside trumpet cleaning before storing away.