Seiko Caliber YT57 Watch Movement

Brand	Seiko Time Corp.
Caliber Number	YT57. YT57A, YT57B
Movement Type	Kinetic, automatic/quartz hybrid
Outside Diameter	27.6mm
Casing Diameter	27mm
Height	4.3mm
Jewel Count	6 jewels
Frequency	32,768 Hz
Accuracy Rating	Less than +/-20 seconds/month
Power Reserve	Up to 6 months
Capacitor Part #	3023.24T, 302324T (rechargeable lithium, MT920 series, previously 3023.44Z)
Hand-Windable?	No
Hand Count	3
Hand Sizes	1.10mm (hrs) / .65mm (mins) / .20mm (secs)
Functions	Central hours; central minutes; central seconds; date at 3:00
Hacking Seconds?	Yes
Country of Manufacture	Made in Japan
Known Models	Various Pulsar, Alba, etc. (Add your watch to the comments below…)

The Seiko caliber YT57 is a kinetic watch movement.

How Seiko describes “Kinetic”:

“‘Kinetic’ is one of our unique watches, which contains an internal electrical generator operated by the kinetic movement of the user’s wrist. The generated electricity is stored in a rechargeable battery that requires replacement less frequently than the conventional cell battery in a quartz watch.” –Source

YT57 VS YT58:

There is a similar caliber YT58 with the main difference being that the YT58 has a day/date calendar and the YT57 just has a date. The capacitor is the same for YT57 and YT58.