Deane, there is a port on the back of your 600 that is currently covered by a square metal plate. It is all the way over to the left side when looking at the back. If you remove the screw you will see this is where the micro sd card gets inserted. As mentioned, this is intended for additional Korg content to be loaded which will be purchased from Korg and will expand the keyboard to play sounds and styles programmed for specific countries. When this expansion micro sd card is inserted, and by the way cannot be copied because it will be encoded with some kind of memory protection, it will take up about 64mb of the internal 96 mb of flash ram. I asked Korg about this and they said that for musicians wanting to load other .sets saved on flash drives, the user will be able to disable the micro sd card from the touch screen so it won't be necessary to unmount the micro sd card from the rear of the keyboard. If the micro card is inserted and being used there will still be about 30 mb of flash memory available to load your own .sets.