Liquid-Plumr Shelfmate is a product from the Drano brand, which is owned by S.C. Johnson & Son, Inc. It is a drain cleaner that is designed to clear clogged drains and pipes. The product is made up of a combination of natural enzymes and bacteria that break down organic matter and grease, allowing water to flow freely. It is safe for use in both kitchen and bathroom sinks, and can be used on all types of pipes.