NOS premium grade stainless steel braided hoses come with –3, –4, –6 and –8 AN fittings ,including step–ups, in virtually any length. They are all Teflon lined with a stainless steel outer covering for strength and resistance to abrasion. All NOS lines are configured for a superior flow to strength ratio. The AN Fittings are color coded for identification: blue for nitrous or red for fuel.