The lead-free wrot copper solder pressure rolled stop coupling is used in residential and commercial systems such as potable water, air conditioning and refrigeration. Options include cleaned and bagged for oxygen service (medical gas). The coupling features solder cups and a rolled stop. The fitting provides a means of connecting two lengths of tube together In addition to its inherent qualities of beauty, durability and low maintenance, copper's reusability makes it an ideal application in sustainable projects. copper fittings are manufactured in an ISO 9001 certified facility and backed by a 50-year limited warranty. Because of its longstanding reputation for innovation and precision in design and manufacturing, is the preferred brand in the industry.