Cal. 3075 is an automatic GMT movement produced by Rolex from 1981 through 1988.
Self-winding movement, bi-directional winding, 28,800 A/h, 27 jewels, GMT function (dual time zone) and date indication.
Used in the model GMT-Master Ref. 16750.
In contrast to the later calibre Rolex 3085 the 24-hour hand is not separately adjustable.
D 28.5 mm, H 6.3 mm
Power reserve 42h