Fuel injection device

Fuel injection device (100) for injecting fuel into a combustion chamber of an internal combustion engine with a first component (1) and a second component (2; 2'), which are screwed together axially against each other by a clamping nut (5), wherein the clamping nut (5) is in threaded engagement with the first component (1), so that a first end face (1a) formed on the first component (1) is pressed together with a second end face (2a; 2a') formed on the second component (2; 2'). At least the first end face (1a) is structured such that no rotation of the first component (1) and second component (2; 2') occurs during tightening of the clamping nut (5).