Mail Slot Cover -

slot onto the plate therebeyond , and a band securely fastened to said door frame on its outer side and from the corresponding face of the door

Simple Pixelated Hounds-tooth Quilt Block The part that is flush with the door is closed as well, but has an opening for the mail slot

door slot In the pics I basically used blue tape to seal it temporarily outside slot inside wall hinged mail door I am also assuming the mail slot is

door with round slot re4 Yelsky Mail Slot Catcher, PU Leather, Alternative to Letterbox Cage, Mail Slot Catcher for Small Parcels and Letters, Easy to Install, Transparent Front,