Wolo's Persuader electric horns are 100% stainless steel 304 non-magnetic grade with a bright polished finish that will not rust. Designed for exterior mounting on any 12-volt vehicle; trucks, SUVs, RVs and boats in a fresh or salt water environment and ideal for almost any weather condition. The Persuader is maintenance free and does not require a compressor or hoses. Includes a stainless steel adjustable trumpet support to prevent vibration, rubber gaskets, and stainless steel mounting hardware.