Mailboxes & Slots with Lockable for Sale

What is the preferred lockable single mailbox for postal carriers? mailbox with slot and lock slot opening: 12” w x 1-14 H Includes a secure lock with 2 keys Locking Mailbox with mailbox drop slot These mailboxes have outgoing vessels within the top slot of the mailbox, it has a double slot, one for outgoing one for incoming Please look

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