Threaded couplings are the standard coupling of choice for connecting two or more pieces of threaded RMC or IMC conduit. They join the ends of the conduit together by threading onto each piece. They can also bond threaded conduit to electrical junction boxes and enclosures or convert runs to thin-wall EMT metal conduit or liquid-tight conduit when paired with chase nipples and connectors.

Self-aligning threaded couplings compensate for minor misalignment when connecting two lengths of conduit. These three-piece couplings include an outer hex ring, threaded ferrule, and hexagonal threaded nipple. They join two pieces of threaded RMC or IMC conduit that are fixed in place and can’t be rotated. They’re often used when a section of conduit has already been installed but requires additional length. The nipple screws onto one piece of conduit. The hex ring and ferrule are placed on the other piece. Once all the pieces are in place, the hex ring slides up and tightens to join the two pieces together.