Bacteriostatic Additive Model 9082 bacteriostatic water preservative additive for use in portable eyewash stations. Four 8 oz. (236.8 ml) plastic bottles are included in one carton. This preservative is to be used only with clean potable water. When used as directed, one 8 oz. bottle will preserve 6 to 20 gallons of potable water for up to six months. Shelf life is up to two years.