For this reason, adapter fittings are essential to the design of many products. A new Series of miniature, leak-tight adapter fittings connects metric-threaded components and pipe threads to imperial (UNF) components. Examples include 10-32 external to M3 or M5 internal; and M5 or M6 external to 10-32 internal; as well as elbows, unions, and extensions. The fittings are for OEM design engineers who must connect Imperial/English/UNF/NPT threaded components to metric threads.