These Hoses are constructed with a stainless steel outer braid that resists abrasion and corrosion, both have a Chlorinated Polyethylene (CPE) synthetic rubber liner with a nylon inner braid that will not collapse under extreme heat, yet is extremely flexible. Superior ProRace hose has the same features as ProFlex but with a specially formulated CPE synthetic inner liner that is embedded with a partial coverage stainless steel inner braid, then bonded together by a full coverage stainless outer braid for 50% more strength.