It is difficult, but not impossible, to plug the HP Connectivity Cable into the HP Palmtop upside down. A little brute strength is necessary to accomplish this feat, and some users are willing to apply it. Both the original 95LX cable and the 100/200LX cable have an HP logo on the top side of the connector. When you slip the connector into the serial port of a right-side-up Palmtop, if you can see the HP Logo on the Connectivity Cable connector, you're OK. If you can't, don't push!