FUNCTION
The protective cover (therefore not referred to as film) is provided only at the edges with adhesive surface. After cleaning the camera surface the cover is so glued only at the edges. The plastic surface is highly scratch resistant. Very nicely done by design - the Sony logo is pasted over with a new one. Although the cover does not rest with the inner part on the transparent glass, the legibility of camera-TFTs not deteriorated.
Any negative implications
Any disadvantage with this type of attachment: If the temperature change, the film moves into the air space between the glass and cover moisture (eg when entering an air-conditioned car). Then one has in the middle a connection between glass and cover and at least temporarily a bubble.