This is a retail authorized dealer display tray / board that would go inside of the glass display cases at the bottom where watches would be showcased on top of them.
I have two of these but the price is for each. Both in similar condition not perfect but certainly collector grade. One board has the seiko logo on the left (shown in this listing) the other board has the logo on the right side (not shown).
Dimensions are seen in pictures but here as well:
28” X 15” X 1”
If you have any questions please ask before buying!