... insulation 3. Good air tightness 4. Environmentally-friendly UPVC Folding Window Specification: 1. Material: UPVC Materials (Model: 60, 70, 80, ... drawing draft for customer information. 4. Glass: Single glass, Double glass, Clear glass, Tempered glass, Refective glass, LOW-E glass, Patterned glass, etc. 5. UPVC Surface Color: ... sheet + Carton + Wooden box / Pallets / Iron Shelf UPVC Folding Window