Smart Roadster 03-05 Original Plug & Play Quality Single DIN Car Radio Installation Set Includes Aerial Adaptor Radio Connection Cable and Radio Cover/Mounting Frame, Anthracite : Amazon.de: Electronics & Photo
Bluetooth-compatible Wireless Phone Call Handsfree Aux Adapter For Smart Fortwo 450 451 Roadster Radio Cd 6 8 Pin Mini Iso Plug - Cables, Adapters & Sockets - AliExpress
New Car Bluetooth 5.0 Module Cable Audio Aux Adapter For Smart Fortwo 450 451 Roadster Grundig Radio Cd 6 8 Pins Mini Iso Plug | Fruugo IN
Smart roadster entertainment upgrades : r/SmartCar