ZGR-1a GPS Unit and Timer Remote Control works with Nikon DSLR and iPhone, Supported Cameras: New ZGR Pinout just launched on Indiegogo. A short url is http://igg.me/at/pinout For location shooting, Shutter release, Long-exposure,Continuous-exposure and Time-lapse It provides GPS functions and help you to control exposure time, interval time and delay time. It also provides remote shutter release function, auto-focus function and a lock function for bulb. Supported Cameras: Nikon D4, D3S, D3X, D3, D800, D800E, D700, D300, D300S, D2X, D2XS, D2HS, D200