Affresh W10549845 Washer Cleaner Designed to penetrate, dissolve and remove odor-causing residue that can occur in all washing machines Specially formulated tablet dissolves slowly, lasting throughout the entire wash cycle and breaking up residue better than bleach Safe to use with Front Load Washing Machines and Top Load Washing Machines - High Efficiency (HE) and Conventional Washers Use once a month to keep your machine fresher and cleaner Septic tank safe