二重ガラス/隔熱ガラスis made of two or more pieces of tempered glass glazing sheets which might be low e or reflective glass or normal float colored glass and use sealant gumming and aluminum spacers which was filled with desiccant together. Insulated glass/ Hollow glass/IGU/Double glazing glass with the perimeter of the spacer that gets in contact with the glass is properly sealed with primary and secondary sealants to ensure it with air/argon tight.