... -structure.com, the glass sealant is installed on the window frame, and not only for lighting the windows open ... and airy, with good water-tightness and air tightnessSpeciation: * Window Glass Option: Clear,tinted,Low-E,tempered,insulated,reflective,frosted ... -saving insulation effect is very significant. Plastic windows and doors UPVC material, lined with steel keel, extrusion, after cutting, welding ...