Slot in Door - What was there?

BLACK POSTAL DOOR KNOCKER WITH MAIL SLOT The advantage of a postal door knocker is that it can be used as a door knocker and a letter plate at the same time

My best idea to prevent this has been to buy a backless wall-mount mailbox with a locking lid and mount it on the inside of the door over the slot, but I can't

slot lucky lady For a sports enthusiast facilities for both out door and indoor sports Members as well as Non-members can book a playing slot as per applicable rules

slot machines for sale cheap bar or bolt used to fasten a shut door, closed window, etc , early 14c , from Middle Dutch or Middle Low German slot , fr5om Proto-Germanic *