Marrex MX-G20M Geotagger GPS System Nikon D7100, D7000, D5300, D5200, D5100, D5000, D3300, D3200, D3100, D810, D800 3-Axis Electronic Compass LCD displays latitude, longitude, & altitude data Maintains last acquired GPS data in event of signal loss (indoors) Built-in battery avoids draining your camera's battery 1 Year manufacturer's warranty