DBZ

There is a mailbox with the letters "AF" on it in West City as seen in the Dragon Ball episode "A Trip to the City", as well as on a mailbox seen in Dragon Ball Z: The History of Trunks.
















A mailbox with "AF" on it in West City
















A mailbox with "AF" on it in The History of Trunks

http://dragonball.wikia.com/wiki/Dragon_Ball_AF