Mercedes-Benz M-Class 2007 Owners Manual - Manual (Page 323)

322
Controls in detail
Useful features
Infrared reflecting windshield*
1 Infrared transparent areas
Your vehicle is equipped with infrared re-
flecting glass, which reduces the amount
of radiated heat entering the vehicle interi-
or through the windows.
The infrared reflecting glass also prevents
the transmission of signals through the
glass by in-vehicle electronic devices, e.g.
electronic toll collection devices.
To allow the use of these devices in the
vehicle, three infrared transparent
areas
1 are placed in the windshield.