It's not rocket science - it only seems that complicated. But now there's a little help from the federal government for parents installing child safety seats. Officials say the new rating system gives parents the information they need to make an informed decision about that child safety seat purchase. In their ABC'S of child seat testing, the National Highway Traffic Safety Administration rated 68 child seats - representing about 95 percent of the seats on the market. Ratings were based on whether assembly was required, labeling , easy to follow instructions, ease of securing the seat, and special features. Child safety seats can offer the best protection for our children, but only if they are correctly installed and correctly used. Thirty nine were given an "A" for ease of usability. None of the seats were rated "C." Last year, the federal regulation known as "Latch" went into effect. The newly designed system was meant to simplify installing child safety seats correctly. While the new system has made it easier, research by the Insurance Institute for Highway Safety suggests - it isn't perfect. The institute tested 6 seats in 10 vehicles. Representing a broad sample of the market. Installation is not always a snap. Not all child restraints fit easily in all vehicles. The easiest fits were in the Chevy Trail Blazer, Dodge Grand Caravan and Toyota RAV4. The agency says the ratings will better educate parents and reminds them every child under the age of 8 should be properly restrained in the back seat, on every trip, no matter the distance. A complete list of ratings can be found at www.nhtsa.gov.