Need floppy card identified

[btomlin@NOSPAM.texas.net (Bruce Tomlin)]

While looking for cheap IIgs machines for parts to eventually get one good 
machine working, I found one that had a floppy card (in slot 6, I think).

The only identifying marks on it are "REV B", "35 306201 00", and "MADE IN 
HONG KONG".  The main chip on this is a "VTCL 27-692-0-0 61H20B56F" on the 
front and "35 3063 01 00", "703010" and "REV B SS" on the back.  The 2764 
EPROM contains only two ASCII strings, "3.5 DISK" and "5.25 DISK".  It has 
two ribbon cables soldered to the board, with 19-pin D connectors on the 
ends.

When I tried to use it from GSOS 6.0.1, I got a message that said I had to 
install the UniDisk drivers.  But they were already installed!  FWIW, I 
was trying to see if it could control an FDHD drive that I had swapped 
into an Apple 3.5" drive case.

Can anybody tell me about this card, how to USE it under GSOS 6, and what 
good it does that someone would have installed into a IIgs?  (Maybe it was 
to control drives without daisy-chain outputs.)