it's a standard SD flash memory card, and can be used in anything else, and formatted in the keyboard to suit the keyboard.

However the machines are now quite old and were only designed for SD cards up to 1GB in size, and smaller cards are becoming obsolete. Larger cards than 2 GB are now SDHC and these will not work. A 2GB card (which can be cheaper than a 1GB nowadays) can be formatted as 1GB in the KN7000 and used normally, and I assume the 2600 will be the same, never having tried it on that machine.

However the good news is that for the average owner it's impossible to fill a 1GB card to its menu capacity with more than 1,980 technics saves and 999 midi files without advanced tricks. And 1,980 does not represent technics songs which could be up to 19,800 if they are short!