The standard glass contained in the Magnum window & doors systems is a special High Performance Low-E glass called Pinnacle Low-e, and a technological breakthrough that means your Magnum windows deliver unsurpassed performance and beauty. Low-E, or low-emissivity, glass is an excellent way to increase your home's comfort and energy savings year-round. How it works Pinnacle Low-e Glass is created by applying multiple layers of microscopic, undetectable metallic coatings to the surface of a piece of flat, annealed glass. The metallic coating helps block out the solar energy in the summer, while accepting and retaining warm, short-wave solar rays in the winter. In the summer, Low-E glass filters long-wave solar radiation - reducing solar heat gain in your home as a result of the sun's direct rays. In the winter, Low-E glass takes on two responsibilities: first it lets warm, short-wave rays into the home for natural warmth; then the Low-E glass helps block the warm air inside, rather than allowing it to escape through the pane, so your heating system runs less to maintain a comfortable temperature. Pinnacle Low-e Glass and an argon-filled glass unit, provide a 49% reduction in solar heat gain compared with a standard clear-glass window unit. Plus, Pinnacle Low-e Glass units reduce harmful UV rays by as much as 72% compared to a clear-glass unit. This helps reduce fading in your furniture upholstery, carpeting and even curtains and drapes. Why Low-E glass is right for you Pinnacle Low-e Glass provides the following benefits: * You save on energy costs for both heating and cooling, as Low-E glass helps air conditioning and furnace units to run more efficiently. * Fading is reduced in interior furnishings such as carpets, drapes and furniture. * You will have purchased an ENERGY STARŪ-qualified product, doing your part to help conserve energy and the environment. Two Available Spacer Systems Standard is "Warm Edge" spacer technology designed to reduce the potential for conduction of cold air from the outdoors, through the traditional metal spacers, to the glass pane. This conduction of cold air not only reduces the efficiency of your energy use, but also creates the conditions for condensation around the glass edges, and the water damage to trim, paint, woodwork and window treatments that condensation can cause The Intercept Spacer System is a warm edge spacer featuring a unique, one-piece metal alloy with a U-Channel design that creates an effective thermal barrier to help reduce conducted heat loss through the window. The sealed, one-piece design makes Intercept spacer stronger and better at retaining insulating gas than many conventional designs. Or upgrade to the optional SST Spacer System features a non-metal design that eliminates cool-edge metal-to-glass construction at the glass edge. This ensures greater insulation at the glass edge - where the window traditionally insulates least effectively - and virtually eliminates condensation at the edges of the window associated with metal spacers that conduct cold air. The SST Spacer System combines a patented structural foam spacer with a seal of hot metal butyl to create a non-conductive edge. The elimination of metal-to-glass contact makes the Pinnacle low-e Glass with SST glass package up to 54% more energy-efficient than ordinary insulated glass units. The non-metal edge also helps prevent seal failure by minimizing the subtle movement of glass panes within the unit.