Instantaneous zero lag vario with bluetooth data connect.
Solar powdered device that rarely, if ever needs charging
Records IGC log files
Transmits both vario and position data over low energy bluetooth connection
The mini has been now replaced by the V5 with flarm (at $750) so the mini 1-4 are very good bang for the buck instruments if you can find them. They allow you to couple with XCTrack or Flyskyhigh software on your phone or other tablet for a very powerful flight instrument