The Pure Drain DEFENDER proprietary disc is a revolutionary product lasting 25-30 days per application. It’s an all-natural, eco-friendly solid composition that contains our proprietary combination of bacteria strains. The all-natural bacteria formulation has a slow dissipation rate when any liquid runs over it. This unique disc is made to go into our Drain Defender System and will eliminate problematic fruit flies by preventing their reproduction. In addition, this product will keep your drains clear from fats, oils, greases, mold, and mildew that can clog your drain lines. It will also remove any foul odors, replacing it with an ocean breeze scent as well. (This product contains no pesticides or chemicals).