KESTREL INTERFACE 4000: The Kestrel Interface is the ideal companion to the Kestrel 4000 Pocket Weather Tracker. With the optional computer interface, data can be uploaded for long-term storage, in-depth analysis and detailed charting. Simply connect the interface cable to the serial port on you PC, rest the Kestrel 4000 on the cradle, and upload your stored data. The included software is easy to use and saves the data in a comma delimited text file for use in your choice of applications: text editor, spreadsheet or database.