EBL Portable Rapid Smart Charger for 8pcs AA/AAA Ni-MH Ni-Cd Rechargeable Batteries 4 LEDs show the charging process.the LEDs display RED when put batteries into the charger;the LED light become weaker and weaker along with the charging process ;automatically switches to trickle charge when charging is complete to ensure maximum battery capacity Very safe products,good at shedding heat,automatically stop charging when voltage up to 3.4V Short Circuit & Input Voltage Detection/Protection AC 100-240V 50/60Hz input for worldwide usage 2.8V DC out shorten the time of charging (most similar chargers are 2.4v)