Charging a powerbank. Charging a phone directly doesn't work as well in the UK and my phone keeps switching charge state as the suns angle of incidence and cloud cover changes. Using a USB charge monitor, the panel delivers a much greater charge to the Anker powerbank than all my other powerbanks. Yes, that's the one. Even on a bright overcast day, it'll easily output over 2 amps. It's a heavy setup though, needs at least a week away from charging sources to start becoming practical to use. I'll be pairing it with a 6'000 mAh Anker for long term use where I'll be charging camera cells, phone, 18650's and maybe a tracker if I move away from Spot and it's replaceable cells. FWIW, I prefer the 2 inputs. Means you can use a not so modern USB output on the train/bus/airport/car/air bnb etc and doesn't rely on such a good quality cable.