Heavy-duty toilet bowl cleaner contains 23% hydrochloric acid for a deep clean. Removes the most difficult rust stains and hard water mineral deposits from toilet bowls and urinals. Ready-to-use formula requires no mixing. Application: Bowl Cleaner; Applicable Material: Ceramics; Enamel; Metal; Chemical Compound: Hydrochloric Acid; Dirt Types: Grime; Lime; Mineral Scale; Organic Matter; Rust; Soil; Stains.