Durable EBL 1.2V AA AAA Ni-MH rechargeable batteries can be charged for 1200 times, ideal for everyday use Safe charger, good at heat dissipation, automatically stop charging when voltage up to 3.4V, with short circuit & input voltage detection/protection Smart charger, automatically switches to trickle charge when full charged to ensure maximum battery capacity, with 4 smart LED lights display the charging process