Complies to the SATRA TM172, EN ISO 20344, BS 3144, GB/T20991-2007 and other standards. Used to evaluate the water vapor permeability of the test sample.Fix the circular test piece on the opening of a test bottle containing a certain amount of solid desiccant . Use the test piece to separate the desiccant in the bottle from the air outside the bottle, and start The water vapor permeability tester. It will continuously rotate, therefore the continuously moving desiccant will absorb the water vapor passing through the test sample. Within a certain period of time, the desiccant in the test bottle will absorb the mass of water vapor.