Quite possible that a standard set has been adapated for a blind person’s use. The pieces have been adapted by hand, to distingish one side from the other. The board has raised squares; very tactile.
Each piece has a hole in the bottom, so that screws can be inserted. The pieces then plug into the holes on the board. Four screws are missing, but I assume that similar examples could be sourced. The screws can be taken out and kept separately.