Coupling device

A fuel injection system of a combustion engine comprising:

• a fuel rail;
• a fuel injector having a central longitudinal axis;
• and
• a coupling device hydraulically and mechanically coupling the fuel injector to the fuel rail, the coupling device comprising:
• a fuel injector cup configured to be hydraulically coupled to the fuel rail and to engage a fuel inlet portion of the fuel injector,
• a plate element configured to be coupled to the fuel injector and being fixedly coupled to the fuel injector cup to retain the fuel injector in the fuel injector cup in a direction of the central longitudinal axis,
• wherein the plate element comprises a main body and a ring element comprising a groove, and
• a snap ring arranged in the groove of the ring element of the plate element and configured to fixedly couple the plate element to the fuel injector,
• wherein the ring element of the plate element is rotatable around the central longitudinal axis of the fuel injector relative to the main body of the plate element.