Internal combustion engine fuel injector

An internal combustion engine fuel injector (1; 51) has a casing (2) defining a nozzle (7); and a shutter pin (16) having an axis (19), and housed in axially sliding manner inside the casing (2) to close the nozzle (7) by virtue of a control rod (23). The pin (16) and the control rod (23) are connected by a connecting device (35; 55), which has an axial seat (36) carried by the pin (16), and a head (39; 59; 69) interposed between the axial seat (36) and the control rod (23), and which engages the axial seat (36) to transmit to the pin (16) a resultant of forces (A) directed solely along the pin axis (19).