The Nikon EH-5b AC Adapter for Various Nikon Digital Cameras is an optional power supply for an array of Nikon digital cameras. It is compatible with the Nikon Coolpix P7100, the Nikon 1 V1, and the D300, D3000, D3000S, D3100, D3200, D40, D40x, D5100, D60, D70, D700, D7000, D7100, D70s, D80, D800, and D90. Plugging the adapter into a wall outlet and charging your camera this way saves battery power and comes in handy when the camera is being used indoors for extended periods of time, such as during studio sessions, while uploading files to a PC, or while playing back media on a TV. The adapter comes with a power cord with US plug for insertion into a power outlet, but requires a power connector (sold separately), such as the EP-5A for the Coolpix P7100, D3100, D3200 or D5100.