The Apollo ExpansionPEX 3/4 in. Brass PEX-A Barb x 3/4 in. FNPT x 18 in. Corrugated Stainless Steel Water Heater Connector was designed for the fast and simple installation of hot and cold water lines to water heaters. After applying pipe thread tape to the MNPT nipples on your water heater, thread the FNPT end of the water heater connector onto the tank and tighten with pliers. Then simply make the final connection to Apollo ExpansionPEX pipe or comparable cold expansion tubing using Apollo ExpansionPEX sleeves or comparable expansion-type sleeve or ring (all sold separately) and your water heater is connected. Features: No-kink corrugated stainless steel construction guarantees maximum flow rate even in tight radius bends Corrosion resistant for greater longevity Constructed of lead free dezincification resistant (DZR) brass and stainless steel for superior reliability and strength Cold-expansion tool (sold separately) is required for installation Listed by IAPMO and listed to NSF 61 Meets UPC, IPC, and cUPC standard requirements Must secured in place using Apollo expansionPEX sleeves or other PEX-A expansion sleeves/rings Maximum working pressure of 200 psi and maximum temperature of 250 degree F Meets or exceeds ASTM F1960 standard Go/no-go gauges are never required To ensure secure connections every time, fittings cannot be dry fit Larger internal diameter of Apollo ExpansionPEX fittings results in a 25% greater flow rate within the system Rated to 200 degree F and 200 psi Item is not compatible with PEXb pipe, crimp-style (ASTM 1807) or pinch clamp (ASTM F2098) piping systems