The 4X20E50561 Lenovo ThinkPad 135W AC Adapter (slim tip) is a powerful and efficient power adapter designed for Lenovo ThinkPad laptops. With its 135 watt power output, it provides fast charging for your device. The slim tip design allows for easy and secure connection to your laptop. The adapter also features built-in safety features to protect against overcharging and overheating. Overall, the 4X20E50561 Lenovo ThinkPad 135W AC Adapter is a reliable and high-performance power adapter for Lenovo ThinkPad users.