Features: 100% brand new and high quality Circuit has high integration level;external circuit is simple,so it has high reliability High Discharge Efficiency of 85%, input 3.7V, output 5V/1A This USB charger board is used for charging, DIY charger Adopted of high quality electronic components, and precision process, ensure for the durability Specification: Input Voltage: 3.7V~5.5V Charging Current: Z 1A Output Current: Z is 1A Output Voltage: 5V BAT Discharge Termination Voltage: 2.9V Preset 4.2V Charge Voltage with ±1% accuracy Discharge Efficiency: 85% (input 3.7V, output 5V/1A) Weight: Approx.8g/0.3oz Package list: 10 x USB charger board