Continental Elite Blue Xtreme High-Performance Hose kits include a variety of upper and lower radiator hoses, by-pass hoses, and heater hoses with Nomex reinforcement. Blue Xtreme is a high, heat-resistant hose designed to provide superior performance over standard coolant hoses. Blue Xtreme hoses give a custom look under the hood while providing miles of worry-free service. SAE 20R3 Class D3, SAE 20R4 Class D3 specifications. Kit contents: (61037HT) Upper Radiator Hose; (63087HT) Formed Heater Hose; (61296HT) Lower Radiator Hose; (63137HT) Formed Heater Hose; (63726HT) By-Pass Hose; (63138HT) Straight Heater Hose.