Where do you have to place the emissions sticker for identifying lowemission vehicles?

The emissions sticker (Umweltplakette) must be placed clearly visible on the inside of the windscreen because this ensures that it can be easily seen by authorities from outside the vehicle. Placing it inside protects the sticker from damage or removal due to weather or cleaning. Stickers on the outside of the windscreen or on the rear window are not valid and may result in fines. This rule helps enforce low-emission zones where only vehicles with the appropriate sticker are allowed.