Earl's Speed-Flex hose is the standard of the industry. Beware of imitations. Speed-Flex hose is intended for use with Speed-Seal hose ends only. No other Earl's Hose End is intended for use with Speed-Flex hose. The use of other manufacturers hose ends is not recommended. The use of stainless braid protected Teflon® brake hose assemblies will result in a firmer brake pedal, improved brake pedal "feel" and better brake modulation. These hoses will not necessarily provide longer life or any other advantage. Since brake actuation produces high pressure with very little fluid displacement, Earl's recommends -3 Speed-Flex for brake systems. Clutch actuation, on the other hand, requires moderate pressure but considerable displacement of fluid. For hydraulic clutch systems use -4 Speed-Flex. In recent years various fuel manufacturers have added any number of new unpublished additives to their blends rendering some of them incompatible with synthetic rubber lined hose. Earl's Speed-Flex Teflon® lined stainless braided hose is impervious to any automotive fuel blend known to us and may be the best choice for use with modern racing gasoline. All Speed-Flex hoses are compatible with gasoline, hydrocarbon fuels, alcohols, nitro-methane, mineral and synthetic lubricants, and high density fuel additives. Sizes -6 and up are carbon lined to dissipate static electricity.Pit Stop USA offers Earl's Speed-Flex Hose - 20 Foot Package - #4 620004 at low everyday prices. Be sure to check out all of our products from Earl's Performance Products including Earl's Performance Products Earl's Speed-Flex Hose.