These are very slim, extremely light weight batteries based on the new Polymer Lithium Ion chemistry.
Everybody loves more pow-wah! And Lithium Polymer batteries offer surprisingly dense power cells, and an increasingly affordable price.
These particular batteries are among the highest energy-density versions presently in production, and come terminated with a standard 2-pin JST connector with 2mm spacing between pins.
NOTE: Do not attempt to charge these with anything but a charger specifically designed for Lithium Ion batteries.
Need something to charge this bad boy with? Try the one of our chargers!