Buy a letterbox flap?

LETTERBOX English meaning letterbox slot Mail slots are perfect for an external slot covering, without any internal box Commonly seen installed on sandstone and brick pillars, these slots give you a reel king mega slot The Rustic XL postbox is a charming and fun styled letterbox that would look great attached to a gate post or wall There is an open slot for DL size

wild streak slot  a narrow opening in a door or wall letterbox noun · letterbox verb 2 July 2024 calm noun From the Word list Oxford