NPT or National Pipe Thread is an American thread type commonly used in a variety of hydraulic and industrial applications. The most common characteristic of NPT are tapered threads, and due to the metal-to-metal sealing method of NPT thread sealant is required in order to achieve a leak free connection.
It is important to note, both the dash and nominal sizes listed in most thread charts do not refer to actual measurements of NPT threads. In order to properly identify NPT threads, please consult the outside and inside diameters of male and female threads respectively. Each of our NPT fittings contain a thread chart in the description for your convenience. Torque specifications and pressure ratings can be found within our resources as well.