A letter-plate (1) is provided that comprises a frame (14), a sleeve (9) and a first flap (7). The frame (14) is adapted to be fitted around an aperture (5) on an exterior side of a door (4). The sleeve (9) defines an inlet (10) and an outlet (11) on exterior and interior sides respectively of the letter-plate (1) and, in use, is adapted to line the interior of the aperture (5). The sleeve (9) is also arranged at an oblique angle (a) to a vertical plane of the door (4) and thereby to said frame (14). The first flap (7) is pivotally mounted to cover the outlet (11) of the sleeve (9) on the interior side of the letter-plate (1). Pivotal movement of the flap (7) relative to the sleeve (9) is restricted by at least one stay (34, 35) connected between the flap (7) and a component (36) of the letter-plate (1) in order to control the maximum angle (b) to which the flap (7) can pivot relative to the outlet (11) of the sleeve (9). Preferably, maximum opening of the first flap (7) is restricted to a maximum angle (b) that is equal to or less than 60°. In addition, preferably the sleeve (9) extends at an oblique angle (a) of between 70° and 75° inclusive to said vertical plane of the door when the letter-plate is in use and slopes downwards from the exterior side to the interior side of the letter-plate (1).