ISO 18418-1:2016 specifies the dimensional requirements of high-pressure liquid fuel pipe end-connections for gasoline (spark ignition) engine fuel injection equipment. It is applicable to externally threaded end-connections having a 60° concave cone (see Figure 1), as well as to the pipe end assemblies of high-pressure fuel injection pipes with outside diameters of up to and including 10 mm (see Table 1).