Get power when and where you need it with the ThinkPad 135w AC adapter. Keep one adapter 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 recharge the system battery. ThinkPad AC adapters are compact, energy efficient (Energy Star V (ES 2.0) rating) and backed by a 1 year warranty. It performs to the exact same specifications as the standard AC adapter that ships with the ThinkPad laptops so is a perfect replacement or spare. The ThinkPad 135w AC adapter is compatible only with ThinkPad laptops with a rectangular"slim tip" common power plug. It is not compatible with ThinkPad laptops with the round, barrel-type power plug.