Smart watch charging with small power is better.
In fact, the common USB charger head specifications on the market are: 5V-0.5A, 5V-1A, 5V-1.5A, 5V-2A, 5V-2.5A, and the most widely used on the market today is basically 5V-2A.
In order to quickly charge a large-capacity mobile phone battery, it is necessary to use a high-power charger. The high power charger charges the current is large, and the voltage is slightly higher. It's actually bad for battery life. Smart watch battery capacity is very small, with trickle charging, more beneficial to extend the battery life. Of course, a high-power charger can also be used.
Use the 5V2A charging head, which is the small white charging head of Apple's earliest generation! With the exception of the Apple watch 7, all watch models do not support fast charging. The official recommendation is to connect the 5V2A slow charging head, which will not affect the battery life of the watch. Apple watch 7 supports 20W fast charging head, depending on your specific model. For reference only
The smart watch uses a 5VUSB interface charger to charge, ordinary smart phone charger can be used, the watch only comes with a standard charging data cable, no charger.