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Swagelok North Carolina | East Tennessee

Your Authorized Swagelok Sales and Service Center

The Difference Between Tube Fitting Caps and Plugs

A cap is a complete Swagelok tube fitting assembly that is used to cap a piece of tubing. It includes a nut, a front ferrule, a back ferrule, and a fitting body that is blank. The blank body allows you to pressure test your assembly before installing it into your system. A plug is used to plug a port on a Swagelok tube fitting, and it has machined ferrules already inside. Like the cap, it allows you to pressure test your system.