The Energizer 1 Hour Charger allows fast charging of up to 4 x AA or AAA NiMH batteries within 1 hour or less. The charger has an LED charge light that shows when batteries are charging and a sophisticated charge indicator displays how charged the batteries are. A 'bad battery' alert displays when the battery cannot be charged. For convenience, the charger features automatic shut-off and will stop the charging process once the batteries are charged. The 1 hour charger features polarity protection, which prevents the charger from charging batteries that are not inserted correctly. It will also detect if the battery is not rechargeable and will automatically stop the charging process. Energy Star certified. Includes 4 x AA 2300 mAh Recharge batteries.