Seiko Caliber 4N30 Watch Movement

Manufacturer	Seiko Time Corp.
Caliber Number	4N30, 4N30A, 4N30B, 4N30C
In-House?	Yes
Movement Type	Quartz, battery-powered
Lignes	4.75”’ x 6.5”’
Diameter	10.8mm x 14.5mm
Height	3.25mm
Jewel Count	No jewels (0)
Frequency	32,768 Hz
Accuracy Rating	+/- 15 seconds/month
Battery Cell #	379 / SR521SW (Silver oxide, 1.55 V)
Battery Life	2 years (unconfirmed)
Hand Count	2
Hand Sizes	.90mm / .45mm
Functions	Central hours; central minutes
Hacking Seconds?	Yes
Country of Manufacture	Made in Japan
Known Models	Seiko Essentials Collection (Mens Refs: SWR049, SWR052, SWR064 / Ladies Refs: SWR044, SWR046, SWR048, SWR053, SWR054, SWR066, SWR078, SWR083, SWR085, SWR091, SWR093) (Add your watch to the comments below…)

The Seiko caliber 4N30 is a small, minimalist, time-only, 2-hander quartz movement with zero jewels.

This caliber is part of the 4N family of rectangular movements with zero jewels. This series of movements includes the 4N00, 4N01, 4N20, 4N21, 4N70, 4N71.