fully welded single hung [Replacement] vinyl window is manufactured with exclusive chambered ThermoBlok™ designer extrusions. These ThermoBlok™ extrusions feature innovative insulating air barrier technology that reduce thermal transference from exterior of window frame to interiors, and “intercept” warm edge glass spacer technology for added thermal protection. These features reduce heating and cooling loads on HVAC systems, providing long term energy efficiency and utility savings to property owners. This value priced series is ideal for home renovation projects, and features easy-to-clean, tilt out sashes that make it popular with home owners.