The 0.25mm nozzle is a direct swap for use on the Budaschnozzle 1.1 hot end. Smaller nozzle orifice and extrusion allows for shorter layer height and higher definition prints.
Video of how to change out the nozzle on your Budaschnozzle 1.1
*Note* This nozzle has only seen light testing and is still currently experimental. We have printed with it succesfully multiple times but it has not had thorough testing.
Specifications
Sources