SharkBite Max push-to-connect fittings allow you make pipe connections with half the insertion effort while withstanding double the burst pressure. Featuring a newly designed stainless-steel retainer, SharkBite Max delivers additional strength and durability while providing a 250 psi pressure rating. SharkBite push-to-connect polybutylene conversion coupling. The fastest, easiest way to transition from polybutylene pipe over to PEX (Coss-linked Polyethylene), copper, CPVC (Chlorinated Polyvinyl Chloride), and PE-RT - wet or dry. Approved to be used underground (wrap required in burial installation) and behind walls without access panels. Fittings are certified to 200 F, 250 psi. Fitting has color-coordinated collars on each end to identify which side goes with which pipe - the gray collar end is compatible with polybutylene pipe and the tan collar end is compatible with PEX, copper, CPVC, and PE-RT pipe. Integral tube liners for polybutylene and PEX installations which means no loose connections. The SharkBite design is certified to NSF/ANSI-61 and ASSE 1061product standard for use in potable water and hydronic heating water distribution. Manufactured to include no more than 0.25% weighted average lead content on wetted surfaces. Third-party listed, compliant with applicable U.S. and Canadian plumbing codes. 25-year warranty when properly installed on PEX, copper, CPVC and PE-RT. Five-year warranty when properly installed with HDPE SDR-9. Patented technology.