... Tube Solar Water Heater, features: 1.ISO9001 certified 2.Copper finned heat exchanger Poduct Name: Medium-Pressurized Coiling Copper Finned Tube Solar ... 2B, thickness: 0.4mm, inner diameter: 360mm3. Vacuum tube: high-efficient vacuum tube(OD: 58mm, Length:1800mm); Hail resistance: 25mm.4 ... 20~80 Degree.6. Heat exchanger: coiling copper finned tube, material: c12000. Fin height: 5~10mm, heat transferring ...