Just to continue the OT on this but in clarification, and again quoting the much loved, and presently much missed, BB in regard to common misconceptions regarding the size limit of image files that can be handled by the FAT32 file system, it is actually exceeded at 4GiB(-1byte) (GiB [Gibibyte], not GB [Gigabyte]). There is a very clear and learned dissertation by Ballebar in regard to maximum image size, maximum MapIDs and maximum map tiles in his Posts #9 and 11 [Only registered and activated users can see links. ]. Some outdoor units can handle up to 4000 tiles, most units only 2025 tiles, but all units are limited by the under 4GiB image file size imposed by FAT32.