SEKONIC Light Meter L-8 and L-28c2

This was previously acquired from a professional photographer. I am listing it because I don't know how to use it and do not plan to use it in the future. The needle moves, but it is unclear whether it is actually usable.
The case shows considerable signs of age, but the main unit is clean with no noticeable scratches or dirt.
As I cannot verify the accuracy of its operation, please accept it as is with no claims or returns.