The hoses are made of sturdy black silicone, which will last longer than standard rubber hoses and has a higher burst pressure rating. The set comes with an upper radiator hose, a lower radiator hose, and a bypass hose, giving you all of the necessary hoses your radiator needs to properly function. To help enhance its performance, the lower hose is nylon-reinforced and comes with a stainless steel spring, which will keep this hose from collapsing and causing other problems. Upper Radiator Hose - 1-7/16" id & 1-13/16" id Lower Radiator Hose - 1-11/16" id & 2-3/16" id Bypass Hose - 5/8" id