Sani Sticks the concentrated cleaning and sanitation sticks you drop in the drain once a month to prevent backups, clogs and nasty odors before they start. Keep Your Drain Pipes Clear and Odor-Free All Year Long! The stick rests in the pipe-trap and slowly releases a blend of enzymes to break down food, grease and other organic materials. Sani Sticks keeps water flowing and pipes odor-free. Perfect for the kitchen, vanity, bathtub and utility/mop sinks. Safe for septic tanks. Includes enough Sani Sticks to treat 2 drains for one year.