1976 Certina D-3 Super ph1000m. ref. 919 1301 41. Automatic movement cal. 919-1, 43 x 46mm. case.

Manufactured by Certina, the DS-3 was selected for service by the Royal Australian Navy (RAN). The back of the case has the NSN (National Stock Number) and issue numbers engraved indicating its use by the RAN.
Originally issued in the early 70s, only a very few of these watches have appeared in the collectors marketplace making it one of the most sought after military issue watches.

The designation DS stands for double-security, referring to the water resistance of the case and the rubber-mounted shock protection of the movement. The DS-3 has a water resistance rating of 1,000 meters.