Mail delivery is provided across the development either via external letter boxes or through the wall, thus reducing the crime problems associated with letter plate apertures, such as arson, lock manipulation and ‘fishing’ for personal items.

Where multiple boxes are to be used within the entrance foyer of shared by a number of businesses or flats, the boxes must incorporate the same design features as a single box. Depending on crime risk it may be necessary for such letter boxes to be located within an ‘airlock’ access controlled entrance foyer, whereby access can be gained by the postal worker through the outer door only.