All SD cards are made to the same standard.

http://www.sdcard.org

Matsushita Electric was the founder of the SD card, and is the parent company of Panasonic.

So the question is, can the FZ20 handle a 1gig capacity card.

My guess is yes, but
I could not find an answer to that question.
Panasonic does sell 1gig cards.

They have a toll free number for support - you can call that number and see what they say.

1-800-272-7033

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