The present invention relates to nuclear technology, and liquid - can be used to prepare the fuel rods and fuel assemblies for the core of a fast neutron reactor utilizing metal coolant. The technical result of the present invention is to reduce the metal content of the fuel rods, and is to reduce the contact stress generated in the fuel rods in the casing of the core in the nuclear fuel combustion. And fast neutron nuclear reactor fuel rods (nuclear fuel disposed hermetically sealed container in the form of a thin wall tubular casing and end component made of steel, wound into a wide pitch helically around the outer surface of the casing, and in and a fixed spacing elements at the ends of the fuel rods) in the casing or end component, spacing element is in the form of a thin-walled tube having a longitudinal through slots along the length of the tube. The present invention, spacing element has a central portion in the form of a tube having a longitudinal through-slot configuration width, an end component in the form of a fragment of a cylindrical casing for welding or the fuel rod plug casing made of thin-walled tube or a thin band having. .FIELD 1