In order to test a
Token Ring adapter without actually
connecting it to the Ring, one must attach a wrap
plug. The plug basically tells the adapter that it is on a Ring, thereby
allowing the adapter to open and
diagnostics to run.
IBM's wrap plugs connect to the
Type-2 cable connector on the back of the adapter and cost $85 apiece.
A wrap plug can be more simply
constructed from an
RJ-45 terminator and two pieces of
wire.