Are you of this file, or is it failing to extract with an error message ?

A "proper piece" for a multi-part file like generally refers to having all the sequence files needed to complete the extraction. If you only have one part of a multi-part set, the archive is considered incomplete and cannot be opened properly. How to Extract Multi-Part RAR Files

: If the extraction fails despite having all parts, you can try the "Repair" function within WinRAR to fix corrupted headers.

: Software like WinRAR, 7-Zip , or PeaZip are the standard solutions for handling these archives.