Seiko Caliber 11A

Manufacturer	Seiko Time Corp.
Caliber Number	11A
Base Caliber	Seiko 1104A
Movement Type	Mechanical, manual-wind
Diameter	15.15mm x 13mm
Height	3.5mm
Jewel Count	17 or 21
Beat Rate	21,600 vph
Lift Angle	Unconfirmed
Power Reserve	Unconfirmed
Anti-Shock Device	Diashock
Hand Count	2
Functions	Central hours; central minutes
Country of Manufacture	Made in Japan or Singapore
Known Models	Vintage ladies Seiko watches (Add your watch to the comments below…)

The Seiko caliber 11A is a basic mechanical 2-hander lady’s small size watch movement.

Not to be confused with the Seiko 11A Indicator men’s wristwatches.

Variations of 11A:

The 11A can be found with 17 jewels or 21 jewels, as well as made in Japan or made in Singapore.

Seiko 11A VS 1104A:

There is a similar caliber 1104A which the 11A is based on. The main difference is that the 1104A has a central seconds hand.

Additional Resources:

• List of Seiko watch movements

Submitted by member Rodders