Pex pipe fittings are used in plumbing systems that involve PEX (cross-linked polyethylene) tubing, which is commonly used for water supply lines, radiant floor heating, and other applications. These fittings connect lengths of PEX pipe, creating secure joints for fluid flow. Some common types of PEX pipe fittings include:

PEX pipe is not approved for use with natural gas or propane. PEX pipe is typically used for potable water systems, radiant floor heating, and some other non-pressurized applications. It is not designed to handle the pressures and chemical properties of gases like natural gas or propane.