The Casio G-Shock DW5900C-9 digital watch was used in the 1st season by nearly all of the main crew members aboard the Seaquest. This fully functional watch was the first G-Shock to include a 3 eye display design and was released in 1990 in the USA. These watches were part of a Seaquest DSV officer's uniform and can bee seen on various actor's left hand wrist throughout various episode's.

Unfortunately I don't know which character this particular watch belonged to.

This prop is part of a pack of Seaquest props as shown in the last posted image.