A power supply for home, one for the office, and one for your bag. This way, you are always on the safe side. The ThinkPad power supply is the ideal replacement charger for your compatible laptops. It is compatible with all Lenovo laptops that feature the common rectangular Slim-Tip connector. It cannot be used with older notebooks that have a round connector. ThinkPad power supplies are so compact that you can easily carry one as a backup in your laptop bag. This 230W power supply has the same performance specifications as the standard power supply included with ThinkPad laptops. The power supply is extremely energy-efficient and comes with a one-year official warranty from Lenovo.