An amazing 7-Zark-7 “cosplay” prop, or at least I assume so given this looks like it is a from a con.
7-Zark-7 was a robot forced into the Sandy Frank butchering of Science Ninja Team Gatchaman in the 1970s called Battle of The Planets.
While Gatchaman is superior, I have a soft place in my heart for 7-Zark-7 and his robot dog 1-Rover-1.