AIO --- basemap-gmapsupp.img = Basemap Layer addr-gmapsupp.img = Address Layer gmapsupp.img = Basemap + Address Layer gmapsupp.img.7z = Basemap + Address Layer compressed with 7z gmt.txt = Tile Info of Basemap + Address Layer maps.html = Map of Tiles gmapsupp-images/ = Basemap + Address Layer compressed with 7z ( last 120 days ) img/ = If you like to make the gmapsupp.img by your own For generating a gmapsupp to copy to your SD-Card you need to run mkgmap like this: java -jar mkgmap.jar --latin1 --gmapsupp --family-id=4 --product-id=45 --family-name=basemap 70013*.img basemap.TYP If you like to make a gmapi-file for Mac OS X Basecamp try this line : gmapi-builder.py -t osmmap.tdb -b osmmap.img -s basemap.TYP -i osmmap.mdx -m osmmap_mdr.img *.img Enjoy!