Heavy-Duty Bowl Cleanse cleans and deodorizes toilet bowls and urinals. The 23% hydrochloric acid formula quickly removes rust, scale and hard water deposits. The powerful detergent system lifts and emulsifies soils leaving the surface sparkling clean. Regular use of Heavy-Duty Bowl Cleanse eliminates heavy build up of dirt and scale in addition to protecting plumbing.Use on vitreous china, toilet bowls and urinals. A special metal inhibitor is included in Heavy-Duty Bowl Cleanse; the formulation protects plumbing with 94.6% effectiveness and will not retard the bacterial action in septic tanks when used as directed.