What is a Seiko 4r38a?

Seiko Cal. 4R38A (commonly called just Cal. 4R38) is a mainstream automatic movement with open heart balance at 9:00. It is also offered by Time Module Inc. (TMI) as Cal. NH38A for use by other watch makers. It is closely related to the date-only Cal. 4R35 and the Cal. 4R37 and 4R39, both of which have a 24 hour subdial at 10:00.

Does Seiko use cal 4R36?

Seiko uses Cal. 4R36 in a variety of models in the 5 Sports and Prospex lines. Seiko 5 Sports SRPD51, SRPD55, SRPD57, SRPD59, SRPD61, SRPD63, SRPD65, SRPD67, SRPD71, SRPD76, SRPD77, SRPD79, SRPD81, SRPD83, SRPD85, SRPD87, SRPD91, SRPD93, SRPD95

What is the difference between Seiko nh36a and 4r36a?

Note that Cal. NH36A is rated at -20/+40 seconds accuracy while Cal. 4R36A is rated at -35/+45 seconds. Seiko produces Cal. NH36 in a variety of color and date window variations with black text on a white dial and day and date wheels or reversed, and with the day and date at 3:00 or 6:00.

What movement does Seiko use?

Seiko uses Cal. 4R38 in a variety of watches, most of which feature an “open heart” to view the balance at 9:00. Most watches using this movement use code SSA in the United States and SARY or SSVM in Japan. Seiko Presage SSA257, SSA258, SSA262, SSA358, SSA359, SSA405, SSA407, SSA409, SSA859