Product Name Set of 2 320Hz 430Hz Super Horns High Power Benz Horn 12V Heavy Sound VIP Sound Aftermarket Horn Silver Hyper Electromagnetic Horn Size Diameter 12.3cm Thickness 7cm Set Contents High-pitched 430Hz / Low-pitched 320Hz with a sound pressure of 110dB. Specifications 12V dedicated Wiring is basically just replacing the positive/negative terminals with the original, but this may vary depending on the vehicle, so please be aware. Included are the main unit and mounting brackets. Vehicle-side bolts are not included, so please prepare them.