Abstract: An improved fuel line insert includes a cylindrical housing extending between oppositely disposed input and output ports, and constructed to include inner and outer chamber surfaces, such that an internal volume is realized in a form of an internal chamber extending between the input and output ports. At least two permanent magnets oppositely disposed from each other and mounted at each magnet's south pole into the inner chamber surface such that each magnets north poles face each other in the chamber in such an arrangement that fuel may flow between the two. The improvement lies in strength of the material comprising the casing and the magnets which is a result of construction of same with a nickel/low carbon steel alloy.