Membrane air dryers dry compressed air with no electricity, no refrigerant, no desiccant and no moving parts. Compressed air passes through a bundle of hollow polymer fibers and water vapor permeates out through the fiber walls, so there is nothing to cycle, nothing to drain on the dryer itself and nothing to hear. They are the practical answer at the point of use: one machine, one lab bench, one paint booth, one outdoor drop, or anywhere there is no power to run a conventional dryer.