Seiko Instruments (SII) Caliber VK67

Manufacturer	Hattori aka Seiko Instruments Inc. (SII)
Caliber Number	VK67, VK67A
Type	Quartz (mecaquartz)
Diameter	13 1/2”’ (30.8mm x 29.10mm)
Thickness	5.10mm
Battery Cell Number	394
Frequency	Unknown (please comment below)
Quartz Type	Tuning fork type quartz crystal
Stem	351177/tap 10 or 351892/tap 11
Hand Sizes	1.50/.90/.32mm
Jewels	0
Functions	Hours, minutes, small seconds, date, central chronograph seconds, 60 minute counter, 12 hour counter
Country of Manufacture	Japan (assembled)
Known Models	Add to the comments below…

The Seiko SII caliber VK67 is part of the hybrid mechanical quartz (mecaquartz) movement line. It is a chronograph movement that uses quartz technology for the main functions of the watch, and a mechanical module for operating the chronograph. Learn more here.

Time Module/Seiko states that the expected accuracy of this movement is less than +/- 20 seconds per month at normal temps. The battery life is about 3 years with normal operation.

Battery replacement:

After installing a fresh battery cell, remember to reset the circuit by touching the AC terminal of the circuit block (look for an arrow labeled AC pointing to a hole) and the switch spring with your tweezers.

Replacement prices of about $35.95 found online.

You might find the caliber VK67 listed as being produced by SII aka Hattori aka TMI (Time Module Inc) aka Seiko Instruments Inc. Learn more about the different names here. Other calibers with the same base movement are VK63 and VK83.

• Official technical guide

The front of the movement