Not necessarily the best accessory for your car.
Window shades that suction on to the window and pull down like a shade really are not safe in your car. Recently my sister found this out. Luckily without her baby in the car.
About 4 years ago the officer that installed my first car seat saw the window shade I had and told me that he doesn't not want that in my car with the baby. When I asked why he explained that in a crash that thing would/could go flying off the window and hit the baby on the head. He recommended that if I really needed a shade, to pick up one that clings to the window, and doesn't have any hard pieces attached to it (ie. suction cups or hard bar that it pulls down from). It made sense to me, so we never used it, and just relied on the tinted windows to do their job. Well a couple months ago I was in my sisters car and saw her cute little shade next to my 8 mo. old nieces car seat. When I told her what the officer had said to me years ago she just kind of shrugged and said ok. A month later her side air bags went off in her car (without the baby in it) and she saw how the thing went flying and landed in the car seat. She immediately took it out of the car and threw it away. She was amazed and had never event given it a thought.
Just something to think about. Everything out there on the market for use with your car seat is not necessarily safe to use with your car seat. Looks are not everything. Please do your research when preparing your child for travel in your car.
There are a ton of resources out there on car seat safety. Here's another favorite I've found.
The Car Seat Lady http://www.thecarseatlady.com/