Insulating gass with built-in electric blinds use the space
inside the glass to place a special set of 15mm

        Insulating gass with built-in electric blinds use the space inside the glass to place a special set of 15mm adjustable electric venetian blinds between two layers of glass. 

         It is actually conbined the insulating glass and adjustable venetian blinds together organically with a completely sealed layer of 28mm.