This is an advanced ETL listed battery charger that can simultaneously recharge up to (16) batteries for select ThinkPad models. This battery charger provides a compact, effective recharging strategy for organizations that want to maintain extra batteries for classes, training facilities, etc. It makes use of the ThinkPad batteries' smart charge and quick-charge features and contains two bays that can be used to completely re-calibrate batteries, helping preserve their effective life and optimum use.