The Nikon GP-1A GPS Unit for D600 DSLR Camera is an accessory for the full-frame D600 DSLR camera. It enables you to geotag your images, so you can record latitude, longitude, altitude and time information. The correlation between pictures and maps is supported by a combination of GPS functionality, ViewNX version 1.2 software available via a free download, and the my Picturetown online photo storage and sharing service. Two accessory cables and a camera strap clip are included with the GPS unit.