I have used many different solar charging products over the years, and I've been fairly impressed by some of them, but I have honestly never seen or used one that works as great as this does. It charges faster than plugging into a wall at home does. I even get decent power from this on a mostly cloudy day with little to zero blue skies, but when there are no clouds in front of the sun, it's really amazing how well and how fast this charges both of our phones or tablets without any issues or struggle. I've been using this for a couple of days and I still can't get over how good this is. I have not been so impressed and amazed by any product in a long time. Incredible stuff.