Question Posters, signs, and window decals on the windshield and windows: Answers Are a fun way to personalize your vehicle. Are permitted if they allow the driver at least a little visibility. Are prohibited, unless they are otherwise specifically required by law. Are permitted only if they do not contain offensive language. Explanation Obstructions on windows are prohibited. No sign, poster, or sticker may be placed on any window of a vehicle, unless it is specifically required by law to be on a vehicle's window. Pass your DMV Written Test with flying colors Take me to the cheat sheet Maine This questions appears in the following tests: Maine Practice Test 55 Maine Practice Test 55