RT Series (Post 2013)
BMW e39 525 530 Horn low tone - 420 Hz
I finally found the receipt with my BMW CAR HORN. It installs plug-n-play right into the same connectors as the OEM horn on my 2016 R1200RT.
sorry if I am being redundant, I know I mentioned this horn in horny-thread that just went by...though I could not...