4-oz. Rust Guard Time-Released Toilet Bowl Cleaner

Stop rust with every flush! Each time-released tablet fights rust and hard water stains for 3-6 weeks depending on frequency of flushing, water temperature and water pressure. Contains no acids, caustics, chlorine bleach, phosphates or dyes and won't attack plumbing like chlorine bleach cleaners can! These tablets won't harm pets, plumbing and septic systems.