Abstract: An electrical actuator subassembly, preferably for use in a fuel injector, includes an externally threaded ferromagnetic metallic body, an internally threaded collar, an electrical actuator, an electrical connector, and a plastic cap. In one embodiment, the electrical actuator is a solenoid, while a piezoelectric actuator is used in a second embodiment. The electrical actuator directly controls a pilot valve member positioned between the metallic body and the injector body, and a needle valve which opens or closes a nozzle outlet at the bottom of the injector. The electrical actuator subassembly is attached to a fuel injector body by mating the external threads of the metallic body to the internal threads of the collar. The collar is attached to the injector body with a groove and snap ring configuration.