MOLDED HEATER HOSE, DAYCO. DaycoÂ Small I.D. Molded Heater Hose is designed to replace OEM coolant hose and provide long, reliable service. Made with the same bends and routing as the OEM assembly, this hose is designed to fit the vehicle precisely. The knitted reinforcement and synthetic EPDM construction provides high strength and resistance to detrimental environmental elements, coolants, and temperature variations of -40Â°F (-40Â°C) to +257Â°F (+125Â°C). In addition to meeting SAE J20R4, Class D-1 requirements, this hose is designed to meet Type EC electro-chemical requirements as specified in SAE J1684. This hose has a €œquick connect€ end assembled onto the hose for fast, convenient installation. With this DaycoÂ product you avoid the hassle of buying a separate connector and clamp and having to install it before the hose can be used.