Energizer Smart Battery Charger is designed to efficiently charge 2 or 4 AA or AAA NiMH rechargeable batteries. It charges batteries at a safe and steady rate, helping to extend their long-term life. The charger features a countdown timer that displays the remaining time until the batteries are fully charged, along with a battery fuel gauge to show the current charge status. It also includes a bad battery alert that automatically stops charging if a non-NiMH battery is inserted, ensuring safety and preventing damage. This package includes 4 AA batteries and is for keeping your rechargeable batteries ready for use. Model Number: CHPROWB4