Windshield and Windows
Your view through windshields and windows must not be obstructed by cracks,
discoloration, steam, frost, ice, or snow when you are driving. Objects may not
be suspended between the driver and the windshield. Labels and stickers or
other devices permitted by state law may be placed on your windshield. These
include state and national park stickers, official safety inspection stickers, and
MNpass electronic toll-collection devices.
Global positioning and other navigation systems may be mounted or located
near the bottommost portion of the windshield.
Driver feedback and safety-monitoring equipment may be mounted immediately
behind, slightly above or slightly below the rearview mirror.
Windshields may not be made of, covered by, or treated with any material
that makes the glass more reflective or reduces the amount of light that travels
through it.
Any window tint material applied to the side or rear windows after
August 1, 1985, must be marked to show the percentage of light that is transmitted
and the percentage of reflection it creates. If it transmits less than 50
percent, or reflects more than 20 percent of available light, it may be used