Get power when and where you need it with a ThinkPad AC adapter. Keep one in the office, one at home, and another in your carrying case for convenient access to power. Just plug it into an available wall outlet to deliver AC power to your compatible ThinkPad laptop and to recharge the system battery. ThinkPad AC adapters are compact, energy efficient and backed by a 1 year warranty. Performs to the same specifications as the standard AC adapter that ships with the ThinkPad laptops. Energy efficient with Energy Star V (ES 2.0) Compatible with ThinkPad laptops with rectangular “slim tip” common power plug Not compatible with ThinkPad laptops with the round, barrel-type power plug.