The SL-2101 is a portable power supply that is supported by an environmentally friendly Polymer Lithium-ion rechargeable battery. How It Works The SL-2101 can be charged by either by using the USB connection on a computer or using a wall outlet. As the unit charges, each of 4 blue indicator lights on the device will illuminate one by one until all 4 are lit at which time it will indicate that it is fully charged by beeping. During this process, a LED indicator will also flash. When pressing the test switch, none of the blue indicator lights will illuminate if the battery is too low and requires recharging. Lightweight (2.6 oz.) and slim (3.4” long, 2.4” wide, .6” thick), the SL2101 is very portable. Just charge it and take it anywhere for a reliable source for charging digital devices. The SL-2101 charges cell phones, IPOD, PSP, MP3 player, MP4 player, PMP, GPS, Bluetooth, digital camera, etc. The SL-2101 will charge products with voltage of DC 5.4 V±0.1V. The mobile charging unit comes with a smart chip to prevent overload and short circuit protection. Shipping & cost:Will ship UPS GND, FDX GND, FDX Home delivery, postal service. Wetry our best toship the same day if payment is received by 4 PMotherwise toship the next day in normal circumstances. No shipping on weekends or holidays. Shipping insurance is covered by us. Breakage in transit will be replaced or refunded to customers' satisfaction. Shipping to POBox,outside of 48 continental states or international locations, please contact us for actual shipping cost