... ,Solar Keymark,UL,SABS offer OEM Name: Non-Pressure Solar Water Heater With Auxiliary Tank(Stainless Steel Series) a) Item no.: RS ... .4-0.8mm, diameter: 320, 360mm.c) Outer tank material: stainless steel,diameter: 420, 455, 460, 470, 480, 500.d) ... Insulation layer: high density polyurethane foaming, thickness: 50-60mme) Bracket: stainless steelf) Auxiliary tank capacity: 5, 8, 10, 20L.g) Installation ...