Seiko's first wristwatch featuring an automated movement was the 11A Indicator. Actually, it was the first wristwatch with an automatic mechanism made by a Japanese company. Seiko's Kameido facility manufactured the 11A, which was made available in late 1955. The A. Schild caliber 1382, a Swiss movement, served as the model for the automatic mechanism utilized in the 11a. The 11a was available in three variants. The first was the ref 14015, which was first released in 1955 and was not a wholly in-house movement because it employed a Nivaflex mainspring. A Swiss-imported E-1 and R antishock mechanism was initially employed in this movement. Seiko's unique S2 diashock technology was installed in the latter batches of the 14015.

Known for its strong anti-shock mechanism (Diashock), which was first implemented in the 1950s to guard against damage to the balancing wheel, is the Seiko Automatic Diashock 21-jewel movement (e.g., 14060N). With a power reserve of almost 40 hours and an operating frequency of 21,600 beats per hour, it ensures seamless operation with little maintenance. This movement paved the way for watches like the Seiko 5 series, which reflected Seiko's drive to create robust, affordable automated timepieces that challenged the dominance of Swiss watchmaking. Collectors value it because it represents dependability, usefulness, and creativity, and it has become a mainstay in tool watches and affordable luxury models.