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?
View attachment 37439
edit
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.