A heavily customised version of DOS 2.5. If you have a Happy drive
then this DOS will boot in the Warpspeed. If you have a memory
expanded machine then it will create a virtual 1050 drive in RAM
which you can treat just like a drive not a ramdisk. It will
format in both medium and single density and can be used with
option 'J' the copy disk function. DOS 2.5 plus also allows you to
use custom fonts with it and lowercase letters are valid in
filenames.