Workbench Release 1.3.1, v34.25 (Kickstart v34.5)
Not a public release
New software only
same as Workbench 1.3
Descriptions & Part Numbers
Two (OFS) DS/DD diskettes
"I got these disks with my Amiga A500 (Rev. 5) a few years back (1990) when I was doing a mobile communication course near Stevenage, Hertfordshire, U.K."
notes that this release was never made public, but it did exist.