A mail slot with security and insulation attachments

A letter box with security and insulation attachments comprising a letter box aperture or mail slot 2 arranged in structure 3, wherein the letter box aperture has an upward slope e.g. an acclivity element 16 and an upstanding strip brush element 8 adjacent the top of aperture 9. In use the slope directs incoming mail 1 upwards and though the bristles of the brush element before falling behind the aperture into a receptacle 58, thereby hindering removal of mail, and introduction of items e.g. liquids. The acclivity element may be formed by plate 16 attached to brush channel 11. Additional security attachments may include locking element 49 Fig 10 to block access through the letter box, and mail container 35, Fig 5 The security and insulation elements are modular and may be fixed or adjustably positioned e.g. via brackets and fixing means 14, Fig 1 and may be used independently or together. The inside perimeter of the aperture may be protected by a sleeve against damaging or vandalism 17, Fig 3. A variety of letter plates A, B or C which hinge up, down, inward or outward relative to the structure wall may be fitted.