Use this cable to connect your iPAQ 3100, 3600 or 3700 series PDA to yourstandard Garmin GPS with a round data connector. (not the Etrex or Emapwhich have a different, square connector.) You can then pass position informationto your iPAQ for use with GPS enabled mapping applications such as TomTomCity Maps and TomTomRoute Planner. The combination of this cable plus a GPS and your iPAQ is much more flexibleand powerful than many of the clip on GPS units for the iPAQ. Click herefor the cable for the Etrex and eMap