[Coco] Backups question

[tonym]

I'm going through some old disks, and found a sequence of 11 360K 40T DS/DD diskettes labelled 1-10 that apparently were a backup of some sort.
On each disk is a sequence of 3 files, ie, first disk has xaa xab and xac. 2nd disk has xad xae and xaf. Third has xag xah and xai, etc...

Anyone remember what backup app did this?
Curious as to what is in this backup set...

Tks

Tony