The Omega 980B watch movement, developed in 1942, was the first calibre with bidirectional rotor winding. It belonged to the pilot series for the family 690 through 699, sharing a similar base-plate. Some samples of this movement were also known to have included a calendar, specifically corresponding to the 693 model. It featured automatic winding and a sweep second function. The Omega 980B was utilized during the period around 1942.