DHD's silicone upper & lower coolant hose kit is a direct replacement for your OEM coolant hoses that may be worn or leaking. This kit is compatible with all 2011-2016 Chevy/GMC 6.6L LML Duramax diesel trucks. The factory T-fittings that are equipped on these trucks are made from plastic and are extremely prone to cracking. DHD's silicone coolant hose kit is constructed of 4-ply heat resistant internal fibers and 5mm silicone, which is twice the thickness of OEM. Because this kit is a direct replacement, it requires absolutely no cutting or modifications, making it a 100% bolt-on upgrade! These coolant hoses are a sure-fire way to ensure reliability for many years!