Clear Float Solar Glass Thickness:  2.8mm, 3.2mm, 4.0mmApplications:Cover glass for solar thermal collector              Glass backsheet for glass-glass photovoltaic modules              Greenhouse roof and wallGLASS DESCRIPTION●MIGO Clear Float Solar Glass is produced by processing high quality clear float glass in continuous tempering furnace. After tempering treatment, it is 4-5 times stronger than ordinary annealed float glass and, if broken, disintegrates into small fragments with dulled edges that are unlikely to cause serious injury. ●Light transmittance is a bit lower than ultra clear low iron glass, but cost is also lower. It is suitable for area having sufficient sun light.MAIN CHARACTERISTICSLight Transmittance3.2mm (1/8"): 90.17%;  4.0mm ( 5/32"): 89.82%Solar Transmittance  3.2mm (1/8"): 84.67%;  4.0mm ( 5/32"): 83.04%Certification   EN12150, EN12600, CCC, SGS, SPFSpecific weight (kg/m²)3.2mm (1/8"): 8 ;  4.0mm ( 5/32"): 10Thickness tolerance  ±0.2mmDimension tolerance±1.0mmDiagonal difference  ≤0.1-0.2%Overall Bow/warp  ﹤0.2%Local warp   ≤ 0.3mm / 300mmFragmentation Test  ≥ 40 particles in 25cm²   EN12150-1MECHANICAL CHARACTERISTICSMechanical strength (N/mm²)    ≥45        Annealed≥120       Tempered, EN12150-1Young modulus (GPa)  73.1        Poisson ratio  0.2    Knoop Hardness (kgf/mm²)  470Density (kg/m³)  2500      THERMAL CHARACTERISTICSHemispherical emissivity (corrected)0.84         Between -18℃and 66℃Expansion coefficient (/℃)  8.6×10﹣6     Between 25℃and 300℃Specific heat0.205        Between 0℃ and 100℃Thermal conductivity (W/m/K) 1         Softening point (℃)   723Annealing point (℃)  544Strain point (℃)  504