cover plate for the belt windup system in roll up shutters (european/german thing)

beware there are several different sizes of these out in the wild 

this one just happens to fit mine

Linked thing on thingiverse is also my own work – key difference: fixed the hole spacing for the belt to passthrough

images show the part in mounted state – the part as such does not need any assembly, any visible hardware is required for actually mounting the part but would be required for store bought alternatives too