Yeah, I bought a Sprinter van for a conversion and wanted to install a Sony head unit so that I had a reverse parking camera screen and CarPlay. Dynamic Sounds sold me a kit to fit it and everything works except for the FM/AM radio! I was certain the adapter they sold me to connect the unit to the car didn't have all of the right pins and after googling to looks like the antenna needs to be powered, which is done by a purple wire that goes into the top section of the quadlock. Unfortunately the adapter only has wiring to the bottom section.pretty specific. Your pic is a "Antenna Turn on for selected Mercedes radios with a quadlock connection
Connect to back of the quadlock on Mercedes Audio 10,15 and 20 radio units to turn on the antenna"
And as such it will only fit certain Merc cars.
Not sure one half the size exists as the double one in that pic is only meant to fit Mercedes
AFAIK all quadlock connectors are 16 pin. What are you trying to connect it to? A Sony stereo?
You could buy one and cut it in half?