Eastman 's Steel-Flex 3/4 '' FIP x 3/4 '' FIP x 24 '' Water Heater Connector is the in water heater supply lines. Its caliber is by what you ca n't see. The supply line a non-toxic plc. gist, a multi-filament adorned nylon reinforcement, a cloudless vinyl out racing shell and a grade 304 unsullied steel adorned outdoor that is designed to prevent kinking and crimping. This flexile supply line impairment and is easygoing to install.