If the Dell is exactly 4cm, the screen bar will fit on it.
If the monitor is larger, you can adjust the support a little with a foam insert.
It is fixed in place with the swivelling arm from behind.
I don't know the curvature of the light. According to the manufacturer, however, it is intended for curvatures of 1000R - 1800R.
I have this light on an LG 34 inch curved .... I wouldn't want to be without this light.
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