(There's no video for Mac OS 7.5.1 Updater (PL) yet. Please contribute to MR and add a video now!)
This is the Polish System 7.5 Update 1.0 which updates Mac OS 7.5 to 7.5.1 and is distributed on a 4 floppy disks set.
Dated April 26, 1995
(3.65 MiB / 3.83 MB)
Mac OS 7.5.1 Updater (PL) / compressed w/ Stuffit
Requires Mac OS 7.5
Emulating this? It could probably run under: Basilisk II