Dayco 71555 RADIATOR HOSE - 1 EA Dayco Brand Hose: This is a Dayco brand curved radiator hose with 13 millimeter inside diameter and 5 millimeter nominal wall thickness Single Black Hose: This is a single black curved radiator hose with 13 millimeter inside diameter and 5 millimeter nominal wall thickness Radiator Hose: This is a curved radiator hose for your vehicle's cooling system Durable Construction: Made from quality materials with 5 millimeter nominal wall thickness for durability and performance