The ST-75 turned out to be a fantastic solar panel/battery combo...we listened and combined our SF-110 5 watt only solar panel and our Mini St-25 solar battery into a very lightweight and portable unit that packs 6 watts of solar power with a 2500 mAh battery. So day or night you can charge your smartphone, GPS, Go-Pro, or other devices that are use standard USB have about 1 amp of power requirement. We were able to squeeze in another watt by adjusting the size of the panels and leveraging some technology.
The ST-75 is just a little bigger than a paperback book and it weighs less then 1/2 pound. Because it folds in half, the solar panels are better protected when not solar charging. Perfect for camping, hiking, travel, or anything else outdoors.
It is one of the few devices that charges your phone at the same time as its internal battery. In the full sun, you'll have your phone charged in less than 2 hours and in less than couple more hours you'll have power to spare to charge your phone at night or when there isn't any sun.
With 2500 mAh you'll be able to charge your smart phone about 1 time. Perfecct for iPhone 4, 5, 6, 6+, the Samsung Galaxy, HTC etc. It will not charge an iPad or larger tablet since those devices need a little more than 2 amps of power. Our ST-50 and PI54 battery packs are perfect for those.