What is the difference between KeyControl 49 and KeyControl 49+?
and KeyControl 49+
are virtually identical in their functionality. Yet, while KeyControl 49 requires
a driver under Windows Vista and Windows 7 (its installation is described here)
and might not fully work under Windows 8 (as explained here),
the successor model KeyControl 49+ does not require a driver at all and works
under all Windows versions directly after connecting automatically (as described
here). Both keyboards can be used without driver under
Linux (check here) and Mac OS X (see here).
In order to identify which model you have, you can see if there is a "+"
symbol printed on the top right side right behind the KeyControl 49 logo.