OEM 2-to-4 channel standard sound adapter harness Fader type:Flat blade (86 and earlier) Rear channel adapter: works with

Rear channel adapter: works with the trunk amp bypass adapter to connect your rear speakers to your radio

anywhere from 2-5 out of 10 OEM radios require additional work

Also available in a 3D printed version for a bit less

No longer available from BMW

2) tape deck maintenance is NOT INCLUDED in the basic service

OEM 2-to-4 channel standard sound adapter harness Fader type:Flat blade (86 and earlier) Rear channel adapter: works withNo longer available from BMW. Plugs into fader connector of a 2 channel standard radio only audio system. With this adapter you can run an OEM 4 channel radio like the CM5908 or KE83 ZBM without a trunk amplifier in a car with 2 channel wiring. Picture is the round pin fader connector version. Flat blade connector version for pre 87 cars also available