Prokure G Fast Release Gas 25 grams 5 Pack is formulated for use between harvests to control odor-causing bacteria, mold and mildew, ProKure G is an EPA-registered ClO2 breakthrough technology. The ProKure G patented vapor delivery system is deep penetrating and designed for use throughout the year. Features & Benefits: Water-activated ClO2 deodorizer, controls odor-causing bacteria, mold and mildew,deep penetrating and patented vapor delivery system, for use throughout the year, fast, easy, effective, great for frequent use and formulated to quickly control.