Go to the nearest Mall there and ask for coin case to mamu. You will just exchange your
strongest pokemon to mamu. Eclavush...

get surf then go to the ship ruins then you will find a few poke balls pick them all up
and go to the womens house next to the game couner then you get it

You go to slateport city and buy harbor mail then go back to the house next to game corner
and talk to the lady and she will give you a coin case (works on saphire and ruby i dont
know about emerald)

you buy a harbor mail in slateport city and then go to the lady next to the game corner
and then talk to her and then finish.

Well, all you do is go to slate port, buy harber mail and give it to a lady in a house in
Mauville.Duh!

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