Knitted reinforcement and all synthetic EPDM construction provides the high strength and resistance to oil, mud, salt, road debris, ozone, coolants, and temperature variations of -40F (-40C) to +257F (+125C);The inner base tube is reinforced with knitted rayon for maximum strength and burst resistance;Meets SAE J20R4, Class D-1 requirements;Meets Type EC electro-chemical requirements as specified in SAE J1684