... SGS 2)Specific Absorption:92%---96% 3)reliable quality,reaonable price Solar Vacuum Tube of 3 layers,More effective, Original and High ... All-Glass Double Tube Co-Axial Structure Glass High borosilicate 3.3 GlassExternal PipeDiameter & Thickness dia.=47±0.5mm &=1.6mm ... 1600mm,1700mm,1800mm,1900mm,2000mm,2100mm Absorptive Coating Property Three layers of Magnetron Sputtering Plating.Cu/SS-ALN(H)/SS- ...