Commodity Integrative Pressurized Solar Water Heater Vacuum Tube : 47mmX1500mm, 58mmX1800mm Amount of Vacuum Tube: 16 / 18 / 20 / 24 / 30 / 36 Material Inner tank: SUS304 stainless steel Outer tank: Galvanized steel alloy Bracket: Galvanized steel alloy Heat insulation layer: Imported polyurethane Heat pipe: straight copper pipe Thickness Inner tank: 1.2mm Outer tank:0.4mm Bracket::1.5mm Heat insulation layer: 50mm Working Temp 99 Celsius degree Working Press 1.0MPa (10 bars) Coloration as per Accessories Assistant tank and electrical heater Certificate ISO9001:2000, CE Warranty 5 years for full system / 15 years for vacuum tube MOQ negotiation Lead time within 15 days for full container at factory Payment Telegraphic Transfer (T/T), Letter of Credit (L/C)