Please note that all solar products are affected by the strength and duration of sun light and batteries by low temperatures. Therefore optimum performance can not be expected at all times. These solar chargers are all well made and have been tested by us. They are battery stores which can be used to power and/or recharge many mobile phones, digital cameras, GPSs, PDAs, iPods and other similar devices. They can all be recharged by their own solar panels or from external sources. Adaptor ‘tips’ are included for most applications and special tips are available from the manufacturers.