National Vinyl manufactures superior insulated clear glass, Low-E, or Low-E with argon gas windows engineered to meet today's demanding energy standards for thermal performance. National Vinyl is proud to introduce Krypto-Lite a revolutionary triple glazed dual Low-e with double Krypton Gas fill. This process provides one of the best insulating windows on the market with an overall U-Value of .20…that's an R-Value of 5! This will allow us to be one of less than 60 manufacturers Nationwide to be listed on the DOE R-5 program.