Descale-It Bathroom Cleaner removes scale rings, build-up, soap scum, and film attached to scale from all bathroom fixtures, counters, glass, fiberglass, sliding doors, shower curtains, cultured marble and tiles. This 100% biodegradable cleaner works without harmful fumes or harsh mineral acids. Descale-It Bathroom Cleaner works! Directions: Simply spray Descale-It Bathroom Cleaner on the surface, let it set for 5-10 minutes for light deposits or longer for heavier deposits. Repeat if necessary. Happy cleaning!