This is a working Klingon tricorder made by Richard Coyle similar to the one used by Commander Kruge (Christopher Lloyd) when on the Genesis planet. It has the correct sequential light patterns that activate when the hood is popped up. All surface detail and the paint scheme are also accurate to the screen used prop. Inside the cover a #7 has been etched into it and Richard Coyle has confirmed that he did, on occasion, serial number his replicas.
More from Star Trek III: The Search for Spock (1984)