An electronic apparatus (1) includes a display generation unit (110) configured to generate a display area (210) in a user in terface (200 4 200 5) the display area being configured to display a 3 D model of a patient s face and a 3 D model of a patient interface device fitted to the 3 D model of the patient s face and a transparency adjustment unit (150) configured to generate a transparency adjustment tool (250) in the user interface the transparency adjustment tool being operable to adjust the transparency of a subset of components of the 3 D model of the patient interface device displayed in the 3 D display area of the user interface.
