Double glazed glass is so called insulated glass or hollow glass, 

It consists of two  pieces of glass. The different pieces of glass are isolated through aluminum tubes whose insides are filled with desiccant. The hollow space is inflated with dry air or inert gas and sealed with butyl rubber, sealant, or structural adhesive, to form glass with dry space. 
 Characteristic:
 Insulated Glass can well insulate heat, insulate sound and lower self-weight of buildings.
 Purpose:
As modern architecture and curtain wall glass develop, especially higher requirements are put forward for energy conservation, insulating glass has been widely applied in buildings, vehicles, freezers, as well as occasions which can provide quite and comfortable indoor conditions at constant temperature and with constant humidity.  
 Specification:
 Maximum size: 2500mm×5000mm(except those made manually)
 Width of aluminum spacer: 6mm, 9mm, 12mm, 15mm, 16mm
 Glass unit thickness: Any combination between 3mm and 19mm
 Quality Standard:
 ISO9001:2008/SGCC/CCC/CE