Most window films can claim that they block 99% of UV rays. UV rays are the source of energy from the sun that can damage your skin, car interiors, and home furnishings. During the summer in Central Florida we pay close attention to the UV index for the day, taking into consideration how susceptible we are to skin damage from sun exposure. But what about the rest of the year? It doesn’t have to be a hot, 90-degree day to cause sun burn.