Plug & Play activation via the OBD II port No need to remove the radio Easy and time-saving procedure Retains functionality of Factory-installed Navigation System for passenger access at anytime Allows onscreen access to Factory Bluetooth Keypad at anytime Allows for Navigation Destination Address Entry at anytime Designed for equipment only unlimited times Vehicle Compatibility: 2017 - 2017 E Class (W213) Navigation / Radio Compatibility: for NTG5.5 Systems Instruction manual: 1) turn on theignition,Car audio all turn on 2) Plug & Play activation via the OBD II port ( below the steering wheel) 3)about 5 seconds ,you hear Beep Beep BeeP....... 4) car audio restart 5) Unplug OBD II port, all finish Note: Installation guide not included, we strongly recommend you professional installation. Please check as much as possible to make sure the item is what you need. Color: As Shown Material: plastic Package Contents: 1 * OBD2 Activator Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.