Specification:1. Inner tank: 0.5mm food grade stainless steel 304-2BOuter tank: 0.4mm stainless steel 304-2B/304-BA2. Insulation: 55mm CFC-free polyurethane3. Supporting Frame: 1.2mm stainless steel4. Vacuum tube: ALN/ALN Absorber, Borosilicate glass 3.3, thickness 1.6mm, hail resistant 25mm.5. Frame Angle: 40-45 degree6. Reflector: Anodized AL. (optional)Terms:1. OEM or Customized design available.2. Payment terms: 30% in advance and 70% against copy of B/L or L/C, For sample T/T 100% in advance.3. Delivery terms: 15 working days after receiving deposit or original L/C.4. Warranty: 5 years, If any leakage of tank, after confirmation, we will replace it for free.5. Minimum quantity: 5 sets. http://www.jxsunfly.com/solar-w...eater-for-flat-roof.html