Made in USA. This zinc plated steel fitting has many uses but essentially, it is a 3-piece reusable -6 TFE hose end with a compression sleeve and compression nut that allow it to be installed onto 3/8 OD tubing. The fitting consists of a reusable -6AN hose end body with brass olive and nut, a compression sleeve and a compression nut. We have used this compression fitting hose end on stainless steel tubing in fuel systems and transmission cooler systems as well as return connections on power steering pumps that have a 3/8 OD tube return connection . Simply cut the bubble off of the steel return tube and install this compression fitting hose end onto the tubing. Note: requires approx. 1" of straight tubing for proper assembly.