... 3.Work Pressure:0.2~3.1MPa 4.Fin space:1.2~3.5mm 5.Tube Diameter:7, 9.52,12 ... ,USA, Japan and Middle east etc. Fin type Description of common materials of this Coil : 1.Fin plate: optical aluminum foil, hydrophilic ... steel plate, stainless steel plate and embossed aluminum plate; Fin type mini copper mini gas water heater