3rd Gen Door Behind Box??

[Pokemon_X]

Does anyone know whats behind that door? it's from fire red on seven island, and does anyone know how to remove the box?
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well there are some boxes and behind them you can see a door and when you press a it says"there is a slight breeze blowing around the box"

 

[Goldenhammerhead]

i'm prety sure that it requires an e reader. like on ruby and sapphire.

 

[Pokemon_X]

oh! ok thanks a lot well then back to training.

 

[Rebellious Treecko]

There's a similar blocked door like that in a house in Sootopillos City in Pokemon Emerald.
You need a certain E-Reader card, but I don't know which one.