If you are listing this in a database or a personal collection, you can use the following "Feature" template:
Part 05 (Requires all previous and subsequent parts to extract) Possible Interpretations of the Code Based on typical file-naming structures: sc25531-THCOTWHP.part05.rar
If you are trying to find the full name of the project, check the .nfo file usually included in the part01 archive or the same directory; it will contain the specific title, release notes, and installation instructions. If you are listing this in a database