Overview Model # R43710 Zep Acidic Toilet Bowl Cleaner quickly removes rust stains, organic and hard warder stains and residue. Its clinging gel formula works longer and harder on vertical surfaces, leaving a clean shine and fresh fragrance. It is safe for septic tanks, drain lines and water-treatment systems. For professional cleaning with less scrubbing Removes rust stains, scale and residue from toilet bowls and urinals Clinging gel-based acid formula Wintergreen fragrance