2-1/2 National Standard Thread x 1 National Pipe Thread AdapterThe 2 1 2 National Standard Thread x 1 National Pipe Thread Adapter is a strong & durable construction made from high quality corrosion resistant materials. Precision machined threads ensure leak proof connection and proper fit. This adapter is commonly used in firefighting, municipal water systems, industrial plumbing, and irrigation applications where a connection between fire hoses and standard NPT pipe fittings is required. Specification Details