Plumber's putty is a type of putty used as a sealant in plumbing. It is a pliable substance used to create watertight seals around faucets and drains. The putty is a basic component of a plumber's toolkit and is often used when replacing plumbing fixtures. Plumber's putty should not be confused with thread seal tape, which is used to seal threaded pipe joints. Plumber's putty formulations vary but commonly include powdered clay and linseed oil. Other formulas use limestone, talc, or fish oil. RTV silicone or epoxy sealants may be used in place of putty.