The CEF27 2XAA 2XAAA with Charger is a microprocessor-based, Ni-MH rechargeable battery charger manufactured by Duracell. It has a size rating of AA, AAA, R03, and R6 and is able to charge two AA sized batteries and two AAA sized batteries simultaneously. It is capable of charging a variety of battery types, including alkaline, Ni-MH, and Ni-Cd. It also has an advanced charging system that monitors the temperature of the batteries, ensuring that they are not overcharged. Furthermore, it has an auto-shutoff feature to prevent overcharging and temperature damage to the batteries.