Clip- on design cleans and freshens with no mess. Antimicrobial protection in the hook to resist odor-causing bacteria. Application: Automatic Toilet Bowl Cleaner; Applicable Material: Ceramics; Enamel; Metal; Chemical Compound: Sodium C14-16 Olefin Sulfonate; Sodium Dodecylbenzenesulfonate; Dirt Types: Soils; Odors.