... -Axial StructureGlass MaterialHigh Borosilicate 3.3 GlassExternal Pipe Diameter & Thicknessdia.=47±0.5mm &=1.6mm, dia.=58±0.5mm &=1.6mm ... ,Internal PipeDiameter & Thicknessdia.=37±0.5mm &=1.6mm, dia.=47±0.5mm &=1.6mm,Pipe Length1500mm,1800mmAbsorptive Coating PropertyStructureCu/SS ... Obtaining a Preset Water TemperatureH≤3.7 MJ/ m²(dia.47)Average Heat Loss CoefficientUlt=0.4~0.6W/( m².°C ...