Check this with your OS. Go to Options then About.
BlackBerry devices that have media card capabilities are: 8100, 8300 and 8800.
They all use a MicroSD card and have the following maximum card GB capacities:
BlackBerry Device Software 4.2.0 Up to 2GB
BlackBerry Device Software 4.2.1 Up to 4GB
BlackBerry Device Software 4.2.2 Up to 4GB
BlackBerry Device Software 4.3.0 Up to 8GB