Have you ever seen a car and thought that its windows were way darker than most vehicles? It likely had accessories called after-market window tint installed. So why do some car owners choose to modify their vehicles this way? It actually depends on the driver, there are several good reasons that people tint their windows.

Why do people tint their car windows?

This modification is a personal choice. Some drivers claim that heavily tinted windows prevent their interior from fading. Others claim that tinting windows helps prevent criminals from seeing what’s inside your car–whether you are driving or left the car parked–according to Kelley Blue Book.

Heavily tinted windows also allow less sun into the vehicle and thus may help it remain cooler. If a car is naturally cooler, keeping it cool means less strain on the A/C system and better mpg. This is why certain officials in California see an energy gain in banning black cars.

Finally, some people just think cars with darkly tinted windows are just plain cooler. Think of it like sunglasses for your car.

How do you tint your car windows?

Because of the cost of tinting, some car owners tint their car windows themselves. Others send their cars to a dedicated window tint shop. Either way, the window tint is a transparent film stuck onto the window like a sticker.

Obviously, tinting windows is a bit more complicated than just applying on a sticker. You must wrap the window tint along the inside of a curved piece of glass. Once its in place, you must cut it to size without leaving an unsightly gap for sun to come through.

Even once you’ve stuck your window tint on your recently cleaned glass, you’re not done. You’ll have air bubbles beneath your window tint. You must knead these out to the edges of the tint to release them.

Is it illegal to tint your car windows?

There is no federal, country-wide law against tinting windows. This means that each state has a different window tinting law.

In most places, you can add some aftermarket tint to your car windows. But there is often a level of tint which is illegal.

Testing the amount of tint is relatively easy; a police officer can open your door and shine a light through the window. What’s more difficult is deciding who to pull over. In some places, it is common for police officers to stop and test most cars with window tint.