Universal 2-tone horn in a set. For vehicles with 12V on-board voltage. Here are the advantages at a glance: New goods with E-mark (approved in traffic) Incl bracket and screws. Without exchanging major modifications for the original horn. The original relay can still be operated. Simple connection via common cable lugs Frequency response of the individual components: 410 - 510 Hz Strong tone Just the right thing if your original vehicle horn sounds squishy or just isn't loud enough.