There are numerous factors which make a high-quality glass, including the thickness, composition and coating of the glass. Windowtech offers glass panes that range from 3-6mm in thickness depending on the need for noise reduction, UV protection and heat-reflection, energy efficiency as well as safety and security. The composition of high-quality windows includes Super Spacer technology, which prevents fogging, condensation and exterior air infiltration. Argon gas-filled windows offer the ultimate in insulation and are often a high mark of superior quality. Low E and Low E 2 coating also prevents in-room heat from escaping through the windows and keeps interior glass panes warmer for increased insulation.