Low-E glass is coated with a microscopic layer of silver that reflects radiant solar energy while permitting visible light to pass through the glass, providing more comfort and lower energy costs. Argon gas works like an insulating blanket between two panes of glass to further improve thermal efficiency and decrease outside sound levels. Choose our ultimate glass package for optimal energy efficiency and maximum cost savings. Ultra Low-E glass offered three invisible layers of silver coating in addition to the superior thermal performance of argon gas.