The only solution approved for cleaning Keurig® brewing systems. Clean quarterly to extend brewer life. Compatible with K-Mini®, K-Duo® Essentials, K- Select®, K-Mini Plus®, K-Elite™, K-Compact®, K-Cafe®, K-Duo®, K-Cafe® Special Edition, and K-Duo® Plus. Removes mineral build-up, fast-acting and odorless. 400 mL.