The Ultralast AA / AAA Smart Battery Charger is a versatile and convenient charger for NiMH or NiCd rechargeable batteries. With the ability to charge 2 or 4 batteries at a time, this charger is perfect for keeping your rechargeable batteries ready to use. The charger utilizes intelligent microprocessor controlled technology and negative delta V cut-off detection to ensure that your batteries are never overcharged, while also protecting against reverse-polarity and short circuiting. The safety timer control feature further protects against overcharging, ensuring that your batteries are always charged safely and efficiently.

The charger also features LED indicators to show the charging status of your batteries - a flashing red light indicates that the batteries are currently charging, while a solid red light means that they are ready for use. With an input of 120V ~ 60hz and an output of 6V 500mA, this charger is compatible with a wide range of devices. It can even be used as a power source to charge certain electronic devices without being plugged in, making it a great choice for those on the go.

Included in the package are a car cord and a USB cord, allowing you to charge your batteries from your computer or even while you drive. The charger is capable of charging AA batteries with a capacity of 2100-2900 mAh in 4-5 hours, while AAA batteries with a capacity of 700-1200 mAh can be charged in 1.5-3 hours. Compact and easy to use, the Ultralast AA / AAA Smart Battery Charger is a reliable and efficient solution for keeping your rechargeable batteries powered up and ready to go.