Yes, the Ugreen Powerbank with 20000 mAh, 100 W and 72 Wh can also charge low-wattage products such as Apple Watches. Here are some important details that confirm that it is suitable for such devices:

- The power bank supports various fast charging technologies, including Power Delivery (PD) 3.0 and Quick Charge 3.0, which enables efficient charging for a wide range of devices.
- It has a charge level indicator and can charge multiple devices simultaneously, which indicates that it is also suitable for devices with lower energy requirements such as smartwatches and fitness trackers.
- It is explicitly mentioned that the power bank also supports smaller devices such as AirPods, fitness trackers and smartwatches.

Therefore, the Ugreen Powerbank should be able to charge Apple Watches and other low-wattage products without any problems.