+ <para>
+ The battery connectors are a standard 2-pin JST connector and
+ match batteries sold by Spark Fun. Other vendors sell similar
+ batteries for RC aircraft using mating connectors, however the
+ polarity for those is generally reversed from the batteries used
+ by Altus Metrum products. In particular, the Tenergy batteries
+ supplied for use in Featherweight flight computers are not
+ compatible with Altus Metrum flight computers or battery
+ chargers. <emphasis>Check polarity before connecting any battery
+ not purchased from Altus Metrum or Spark Fun.</emphasis>
+ </para>