SharkBite? PEX pipe is a cross-linked polyethylene pipe for use in a wide range of residential and commercial plumbing applications. Manufactured without an oxygen barrier for potable water systems and with an oxygen barrier for radiant floor and hydronic heating applications. A repeating SharkBite? imprint pattern provides a visual aid to determine if the pipe has been inserted all the way into the SharkBite? push-to-connect fitting. This feature only works if the pipe is cut between the SharkBite? imprint pattern.