The Seiko caliber 2906A is an automatic movement found in ladies Seiko watches. It has 17 jewels and a hi-beat rate of 28,800 vph. Made in Japan.
Caliber 2906 Vs 2906A:
2906 and 2906a are the same. The dial and caseback of the watch may reference 2906, but the rotor will say 2906A. The letter signifies the evolution or version of the movement, starting with A.
Features listed in old Seiko Documentation:
Thin automatic day and date lady’s watch – Having the technically excelled mechanism as with Cal. 2706 which has obtained a worldwide reputation for its high precision mechanism and variety of functions as a lady’s watch, this watch offers a greater variety in design by making its movement slimmer than Cal. 2706.
Movement of highly stabilized time accuracy – This movement is specially designed on the basis of the highly reliable movement mechanism of Cal. 61 series which have been marketed with a reputation on the overseas market.
Easy-to-use day/date setting device – The day/date setting can be simply operated by turning the crown clockwise or counterclockwise after pulling out the crown in the 1st click position. At the same time, either of the two languages provided can be easily set to indicate the day of the week by the bilingual changeover system.
Simplified movement structure – A sophisticated design of the watch movement has made it possible to reduce the number of parts and made it possible to adopt the new balance spring holding device. Thus, the simplified movement structure facilitates easy after-servicing.
Crown Position Functions:
0 (against the case): Clockwise = Manual Winding / Counterclockwise = Nothing
1 (pulled out one click): Clockwise = Date setting / Counterclockwise = Day setting
2 (pulled out two clicks): Time setting clockwise and counterclockwise