We purchased this device because it seems the battery often dies when you're nowhere near a wall to charge it, and carrying a spare battery doesn't always help, so this was a great idea! As an added bonus the solar charger can also charge the Game Boy Advanced (at the same time!!). We were highly amused that the solar charger is basically the shell of a GBA with solar panels where the screen and controls would be. That means it fits in a standard game carry case. It's also a fantastic idea for military members headed downrange where there's plenty of sun but not always plenty of electrical outlets. Very economical, eco-friendly, and convenient.