The .part3.rar suffix indicates this is the third volume of a split archive . To successfully extract the contents, you must have all other parts (e.g., part1.rar , part2.rar ) in the same folder .
Another lightweight, open-source option for extracting various archive formats . Security Best Practices sc23372-BATT1UEv3110715.part3.rar
A popular, free, and open-source alternative that supports RAR extraction. It can be found at 7-Zip.org . sc23372-BATT1UEv3110715.part3.rar
The original software for this format. You can download it from RARLAB . sc23372-BATT1UEv3110715.part3.rar
To see what is inside, you will need to use a file extraction tool: