If prompted for a password, it is likely "ziperto.com" or another common password from the source site.
The software will automatically detect and pull data from the other parts to create one single file. RLUE-NSwTcH-NSP-Update176-Ziperto.part1.rar
Because the filename ends in .part1.rar , it is part of a split archive. You cannot extract it unless you have all subsequent parts (e.g., part2.rar , part3.rar ) in the same location. If prompted for a password, it is likely "ziperto