Cardinal LoĒ³-366® glass is the ultimate performance glass. LoĒ³-366® delivers the ideal balance of solar control and high visibility. It’s also the one glass you can use to be compliant in every ENERGY STAR zone – in a double-pane window. Couple it with LoĒ-i89®, and you’re compliant in the North. Its low SHGC makes it compliant throughout the rest of the country as well.