North Star pays unwavering attention to the basics, using only high-quality vinyl extrusions manufactured in our advanced facility. The AAMA-certified extrusions (also known as profiles) are tested and measured on an hourly basis by a computerized system that ensures specifications are always met, or exceeded. At North Star, every window uses energy-saving Low-e glass. The Super Spacer® technology employed in every North Star window resists condensation, boosts R-values and lessens noise. And we back every window with a transferable, limited lifetime warranty. Our windows are best because we build them that way!