Printed Encosure MK3 with stronger sidewalls

I like the idea of a simple, temporary cover for the rather rarely used "difficult" materials such as PMMA , nylon or ABS.
However, the thin plastic film seemed too "improvised" to me, so I came up with the idea of thick PET film, which I discovered by chance in the hardware store.

I added the missing infill elements for the smaller back side part that wer missing in the remix of @Mrak3D 

Instead of a thin plastic foil I  made side wall pieces with a strong 0.72 mm PET foil - sold as “PET glazing film by the meter” from the hardware store -and taped them together with fabric tape.

The front side can be easily folded upwards for loading aud unloading.

I printed the infill elements with PMMA, the frames with PETG. 

One problem was that the PET film on the roll was very warped. After cutting, I smoothed out the individual parts with an iron between two cloths. Attention, not more than level 2 of 3, otherwise the surface becomes cloudy, probably because the structure of the cloth melts in.