The X-LC™ 31880DG four-line degasser eliminates dissolved gases in up to four mobile phase inlet lines by passing the solvent through a special fluoropolymer membrane tube with the pressure outside the tube reduced. Because degassing by membrane separation is carried out under such mild conditions, the process has virtually no effect on the composition of the solvent. In addition, this method is high efficient, yielding redults similar to that of degassing by the helium purging method. Since all parts that come in contact with liquid are constructed of non-reactive.