Dear sir we are the manufacturer of high purity oxygen, which is substitute for imported 99.999% oxygen. impurities - thc> 0.1 ppm co2>0.5 ppm ,ar> nil ,h2 -nil ,h2o >1 ppm co -nil and n2>15 ppm kindly contact for your requirement with unmatched price shashidhara k.s. bhuruka gases ltd calibration gas division 9886171945