Z13 filename extension are used by archiving and data compression tools. Z13 file is the 14th part of multipart ZIP archive (the first part uses ZIP suffix, the second Z01 suffix, the third Z02 suffix, etc.).

Archive splitting is commonly used when a large files must be stored on multiple smaller storage devices. In order to recreate the whole archive, all parts of the archive must be present. Unpacking is initiated by extracting the ZIP part (or EXE if its a self-extracting archive).