Whink® Rust Guard®. Won't harm pets. Outperforms all major bowl cleaners! Stops rust with every flush. Safe for plumbing & septic systems! 2 tablets. No other toilet bowl cleaner works like RustGuard!®! Its unique formula is specifically designed to prevent rust and hard water stains - with every flush! Outperforms all major bowl cleaners! Safe for plumbing and septic systems. Won't harm pets. Safe for use in white and colored toilets. Pet owners: although RustGuard® will not harm pets, it is not recommended that pets be allowed to drink water from the toilet on a regular basis. Comments, questions: call weekdays 9-4 CST toll-free 1-800-247-5102. www.whink.com. ©2015 Whink Products Company.