BrassCraft® Copper-Flex™ 3/4 in Female Iron Pipe inlet x 3/4 in Female Iron Pipe outlet water heater connectors. Used to connect the water supply to your water heater, this connector features an integrated dielectric sleeve, the sleeve isolates dissimilar metals within the waterway, where galvanic and electrolytic corrosion have their greatest potential. This separation provides complete protection against galvanic corrosion that can deteriorate the connector and cause leaks.