You'll never have to throw away a can of thickened finish again. Bloxygen™ Left Over Finish Preserver is an inert gas that is sprayed into the can prior to closing the lid. This heavy gas displaces the oxygen from the can preventing the finish from thickening. Bloxygen™ will work on most finishes. One can will treat approximately 75 quarts of finish. Does not contain CFC's, VOC's or added propellants. 0.41 oz.