I installed my new horn today. First of all, the removal of the OEM horn was very easy - a single nut held the horn on, and the wiring connection simply unplugged. The OEM horn was also very easy to get to. Nothing else had to be removed. Then, the installation of the Hornig horn was equally as easy. The Hornig kit had all that I needed - the horn and a short wiring harness. The new horn attached to the same bracket that the OEM horn came from. The wiring harness attached to the new horn with two connectors, and then plugged into the original BMW connector. Within a few minutes, the job was done. Then, it was time to test the horn. My wife rides a '23 BMW R1250RS, so she sounded her horn, then I sounded mine. Without a scientific measurement, I can safely say the Hornig replacement horn was substantially louder than the OEM horn. Twice as loud? Not sure, but it was a LOT louder. So in conclusion, I'm very happy with the new horn. Sierra BMW has been great to work with the entire time, the horn was delivered on time, the cost was reasonable, and the installation was a breeze. This is the easiest five stars I've ever given.