Everyone has that "good charger" in the house, the one that seems to get your phone from 4% to 100% in record time. But it's a bit of a mystery isn't it? Why does one charger work great while another doesn't seem to budge at all. It has to do with whether that charger supports USB Quick Charge, and of course the output current ability and the length and quality of the cable used. All things that an electrical engineer could work out with a multimeter and some notepaper - but who has time for that! 

This Black Woven USB A to USB C Cable with 66W Watt Display makes determining the charger setup easy: look on the end of the USB C plug to read the amount of power going into your phone. ~3W is a standard 5V / 500mA draw, 5-7W is when you can get 5V / 1A and higher wattages correspond to quick-charge capable setups. 

Using it is simple: if you have multiple outlets or chargers available, pick the one that gives you the highest Wattage number!

Or use it as a simple power monitor for your single board Linux computer or other high-current-raw USB device.

It is 1 meter / approx 3 feet long so it won't drag down your current but still gives enough length to reach any port.