For every hour you charge your mobile device with the TravelSol 2xit will give you 1 to 2 hours of talk time. The TravelSol 2x comes with 4LED settings, which will show you how much sunlight your panel is receiving. LED 1 means the product is not charging well. LED 2 to LED 3 means the product is charging good. LED 4 means the product is charging super fast. Most IPhones or Smart Phones will charge between a LED 2 and a LED 4 depending on the weather conditions that day.