A full-scale version of EXIST on the International Space Station (ISS) would include 8 m2 total area in 2 large coded aperture telescopes with combined 80° x 160° field of view. EXIST-ISS could be mounted on the International Space Station (ISS), as shown above. It would provide full-sky imaging each orbit and achieve the ultimate hard x-ray survey sensitivity: a factor of ~1000 better than the only previous (HEAO-A4; 1979) all sky survey.