Dielectric union, galvanized steel and brass with nylon insulator ring. Each union end connects to the corresponding pipe of a compatible metal. The insulator ring stops the electric flow that occurs when two the dissimilar metals are joined. The joint can also be removed for applications that require future removal or maintenance of the pipes. Designed for use with water, oil, glycol mix in residential or commercial residential plumbing, commercial plumbing, heating systems. Refer to specification sheets for additional technical information. All Webstone products are backed by a limited lifetime warranty.