This handy kit includes both our USB charger and an 900mAh LiPo battery. The USB LiPo Charger is a basic charging circuit that allows you to charge 3.7V LiPo cells at a rate of 500mA or 100mA per hour. It is designed to charge single-cell Li-Ion or Li-Polymer batteries. The board incorporates a charging circuit, status LED, selectable solder jumper for 500mA or 100mA charging current, external LED footprint, USB input, mounting holes, and various holes for your own connectors. It includes a single JST-tpye connector which connects directly to our LiPo batteries. The connector comes unsoldered, so you can use it or not. There is also a 'SYS OUT' which allows you to connect the charging circuit directly to your project so you don't need to disconnect the charger each time you want to use it. Also included is a 900mAh LiPo battery. This is the highest energy density currently in production. Each cells outputs a nominal 3.7V at 900mAh! Comes terminated with a standard 2-pin JST connector - 2mm spacing between pins. Battery includes built-in protection against over voltage, over current, and minimum voltage. Note: Be careful with the JST connectors. They can stick in pretty good and tugging on them can damage the connector.