The ThinkPad 170W AC Adapter is the perfect replacement or spare power supply for your compatible ThinkPad laptop. ThinkPad AC chargers are compact so they are highly portable - perfect for busy professionals and travelers. They are energy efficient with an Energy Star V (ES 2.0) rating. They perform to the exact same specifications as the standard Thinkpad AC adapter that came with your ThinkPad laptop. This 170w adapter is only compatible with ThinkPad laptops with rectangular “slim tip” common power plugs. It is not compatible with pre-2013 ThinkPad laptops with the round, barrel-type power plug.