Guardian Industries' Performance Plus II Low-E can save significant energy dollars when incorporated into a window such as the Philips Marquee 9000. This high performance low-E coating is designed to keep heat where you want it, so warm rooms stay warm in the winter, and cool rooms stay cool as the summer sun is reflected away from conditioned interior spaces. Homes with high performance low-E glass use less heat in the winter and less air conditioning in the summer, resulting in significant consumer energy savings.