Ok, i see what you were getting at now and i agree, it's theoretical maximum. As you may get less, all the more reason to use a 4GB SDHC card instead of a 2GB SDSC one in such devices. That way you'll maximize the image size right up to the FAT16 limit of 2,147,483,647 bytes .... or if using a device that can see up to 4GiB images in FAT32, utilize an 8GB card to maximize to the FAT32 limit of 4,294,967,295 bytes. Also, in some old devices that do refuse to use a 4GB card simply format as FAT16 then create a partition of 2GiB leaving the rest allocated.