Both 40w and 66w refer to the highest output power, and the average power of 66w May not be as high as 40w, so 40w May be faster
The difference between 66w fast charge and 40w fast charge? 66w fast charge and 40w fast charge, the difference is that 66w is 26w more than 40w. The speed of his network here represents power, and generally speaking, the more power, the faster he can charge, and the less power, the slower the charge. Because 66w, you are 50% more than 10w, so its charging speed will also be 50% faster than 40w.