dumb USPS mail question- outgoing mail door slot?

Uses include commercial mail slots, residential mail slots, as well as vertical mail slots This section of mail slots inlcude options for both door mail slot

Shop door mail slots from Ace Hardware Our assortment of high-quality door and wall mail slots includes a range of materials and colors to match

door slot While both traditional mailboxes and door slots allow for the reception of mail, only traditional mailboxes support outgoing mail The one-way

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