How to identify which machines gray system installation disks are for?

How to identify which machines gray system installation disks are for?

I have about 20 different gray Macintosh system installation disks that I have acquired over the years. I only marked a few of them with the matching machine identification. Doing a web search for the 2Z691-xxxx-x numbers on the disks gives very little information. Does anyone know where to find a list of which disks work with which machines?