Paul Mika wrote (or quoted from eBay?):
Apple 3C
The first attempt at Apple to add a hard drive to an Apple II.
More like Apple was wandering around and trying to figure out what kind
of computers they wanted to make and went to a hard drive.
pretty good since everyone uses a hard drive now.
AT&T or someone attempted to use a regular audio cassette for the same
reason. Wat too slow!!!
There is still software out there.
Seen on ebay.
Aple's first attempt to add a hard drive to an Apple II was the Profile,
introduced in 1982. Originally they had a 5 MB model, and later
offered a 10 MB model. The Profile was used on the Apple ][ and Apple ///,
with a different interface card for each. Later it was used on the Lisa,
using the standard Lisa parallel ports. There was a prototype of an
internal Profile 5MB drive for the Lisa, but it did not ship as a product.
Instead Apple designed a new "Widget" 10MB internal drive. There was
also a prototype of an external Widget drive for AppleBus (which was
renamed to AppleTalk, then later to LocalTalk).
It's true that the profile was not very fast, but then most hard drives
on microcomputers back in 1982 were rather slow.
Third-party hard drives for the Apple ][ appeared before Apple's Profile.
I'm not sure what any of this has to do with an "Apple 3C", whatever
that is.
Eric