THE FACT ABOUT POWERBANK WITH BUILT IN CABLE THAT NO ONE IS SUGGESTING

Even though you link an iPhone X rated at 18W to your USB-C port, it’ll only draw the expected output. So yeah, you'll be able to relaxation apart concerns of overcharging and overheating.The USB-A ports are optimized to charge lower-electric power gadgets likewise. So yeah, you can be assured even though you hook your earphones into the 15W port