Vent shades, rain guards, window vent visors, whatever you like to name them, are the exact same parts that perform the exact same function. These are the pieces of acrylic plastic that attach to your vehicle right over the top of the windows for a number of reasons. First and foremost reason is to allow those windows down a bit to let the air pass inside the car while it's raining or snowing outside. Also, these parts are second to none when it's too hot outside to have your windows fully open but you still want fresh air circulation in the interior. One more great advantage to be mentioned when describing these effective add-ons is their easy and quick installation.