This cerium-added quartz tube can effectively prevent all radiation of UV-B and UV-C ultraviolet and most radiation of UV-A ultraviolet .It is the best materials to prevent UV with best transparent performance. It can be used to make quartz halogen lamp , gas discharge lamp and other UV lamp-house , which will effectively protect human and object from hurt of ultraviolet and maintain the best efficiency of light transmission. Dimensional Tolerance Range of OD OD WT Siding Out of Round Bow/1220mm ≤6mm ±2.0% ±10% 12% 2.0% 2.5mm 6.00-15.00mm ±1.25% ±8% 10% 1.5% 2.5mm 15.00-20.00mm ±1.25% ±10% 15% 1.5% 2.5mm 20.00-25.00mm ±1.25% ±10% 15% 1.5% 3.0mm 25.00-30.00mm ±1.35% ±12% 15% 1.5% 3.0mm Chemical Composition Unit: ppm Cr Ge Fe Mg Ti Ca Al Na Li K OH ＜0.5 ＜0.4 1.5 0.5 2.5 2.3 25 2.5 0.6 2.5 1-50 Physical Properties Density 20℃ kg.m-3 (×103) 2.2 Coefficient of expansion 25-300℃ ℃-1 (×10-6) 0.58 Softening point ℃ 1620 Annealing point ℃ 160 Strain point ℃ 1060 Youngs modulus Pa 7.1×105 Spectral Transmission at 1.0mm Thickness Nm ＜220 230-280 290-330 315 350 380 590 780 % 0 ＜19 0 15 88 92 93 93