What is the preferred lockable single mailbox for postal carriers?

What is the preferred lockable single mailbox for postal carriers? mailbox with slot and lock The door contains the aperture or posting slot It is hinged, should display It is fitted with a brass security lock on the inside The contractor mailbox door slot Greetings Wall Mounted Mailbox + House Numbers, Lock Included, Outgoing Flag, White, Black Fontby Modern Aspect $220 Free Shipping Sponsored

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