Security system for letter box flap comprises horizontal hollow square profile bar which carries vertical metal plates to prevent flap from being opened, bar and plates being fastened to box by bolts and wing nuts

摘要

The security system for a letter box flap (4) comprises a horizontal hollow square profile bar (9) which carries vertical metal plates (10). These prevent the flap from being opened. The bar and plates are fastened to the box by bolts (12) and wing nuts (14).