The iPhone12 has fast charge and slow charge charging power size is completely different is a very big difference, fast charge and slow charge the most essential difference, is the use of the charger output power is completely different, the charging data line is also different, charging time is also fast and slow, this is the biggest difference between the two, I hope my answer can help.
The fast charge of 12 is the amount of P that can be charged in half an hour, and the slow charge may be , which will be slower