Patco Toilet Bowl Cleaner is a concentrated acid based stainless steel and porcelain cleaner. It is powerful purple liquid used in restrooms with heavy traffic, hard water scale, problem soils or infrequent maintenance. Patco Toilet Bowl Cleaner has a high acid content which dissolves and penetrates even the toughest lime deposits, uric acid deposits and unsightly rust. Excellent for cleaning urinals and toilet bowls. This product won’t harm septic systems.