Ostracion cubicus-Boston Bean Box Fish
A box fish that isn't reef safe, also they are ich magnets so you need to be careful when you place one in your tank. Usually you see very small ones for sales, about the size of a nickel, but they do grow and reach about 6"-8". You need to be careful as they contain toxic and can release it into the water when bother or die.

Because of their beaks they shouldn't be kept in acrylic tanks, as they can take bits out of the acrylic and leave scratches.