Seen from the front and on top, the fold in the metal roof sheet that functions as gutter. Also visible the side-wise overlap of this roof sheet to close the gap with the naboring module.
There is also a lengt-wise overlap to bridge the gap with the module that is attached to the here visible end of this module.
In use the beam of roof elements will be inclined downwards to make rain water run of properly.
Also note the overlap of the ceiling matting (white)