The .at5 file extension is associated with mapping and global positioning systems programs produced by Lowrance, a software and electronics manufacturer for anglers, recreational boaters and other sports enthusiasts. AT5 files work primarily with Lowrance MapCreate and NauticPath programs, but can be opened using other applications from the same manufacturer. These files are meant to work with the company’s proprietary GPS and fish finder systems, and are not compatible with ordinary computers. Writer Bio
