I'm looking for an adjective to refer to the space available on SD cards or USB sticks (the amount of Gigabytes available, to be clear). Specifically, a shorter version of this:

> You need an SD card with a lot of space.

That's still kind of ambiguous. I'm not sure what adjective would be correct here: 

> You need a *large*/*big*/*high capacity* SD card.

When I use *large* or *big*, it sounds as if I'm referring to the physical dimensions of the medium. *High capacity* is my best guess at the moment, but it still sounds wrong. Is there an accepted adjective for this meaning? If not, what is the best short phrase that I can use instead?