Swivel joints are a live swivel which means that even after the connection is tightened, they will still swivel.  The use of Swivel joints allows for better system plumbing and prevents hoses from twisting and kinking.  This allows for less downtime and therefore long term cost savings.  Swivel joints are available in straight and 90* configurations as well as plated steel and stainless steel.  Please inform us of your application so we can recommend the proper body material as well as o-ring materials to ensure proper long-term service life.