Looks like 1980 state of the art gear, when windsurfing was the hottest sport on the planet, a board like that usually spun out due to fin cavitation after reaching terminal velocity.
when windsurfing was the hottest sport on the planet
Sh1t.........you would never know hey?
Well I know, shows my age I guess, made my first windsurf board almost the same, but had a "hump"on the back for better foot placement. These days you find stuff like this on the tip. Or a revival as kite race board?