Sierra Water/Heater Hose 1/2″ – Black Sierra1350 Water/Heater Hose is fabric reinforced and has an EPDM tube and cover. The hose isresistant to mild chemicals, heat, cold, ozone, and saltwater. Specifications: I.D.: 1/2″ or 12.7mm O.D.:13/16″ or 20.6mm Wt. “C”:19 Working Pressure:200 PSI Temperature ranges from -40F – +212F Application: This hose is primarily used for engine heater hose, heat exchanger, A/C circulation, and drain lines.