"SAE" flanges are manufactured in accordance with the mounting dimensions and O-Rings of SAE J518 specifications, either Code 61 or Code 62, and ISO 6162. Stock flanges include socket weld, butt weld, NPTF and SAE straight thread connections and are available as reducers, in-line & elbows.Companion (flat-faced) flanges, for unions or converting split flange connections to pipe and tubing, are available with either inch or metric threads.