Seiko Instruments · Japan

Seiko NH34A

Seiko Instruments NH34A automatic GMT movement used in accessible GMT watches. Islander lists its JFK ISL-206 with a Seiko NH34 automatic GMT movement, handwinding/hacking, and roughly 40 hours of power reserve.

3

Hz

24

Jewels

40h

Reserve

1

In catalog

Technical specification

Manufacturer Seiko Instruments
Origin Japan
Type Automatic
Beat rate 21,600 bph · 3 Hz
Jewels 24
Power reserve 40 h
Hacking seconds Yes
Hand-winding Yes
Date Yes
GMT Yes
Chronograph No

FAQ

Is the Seiko NH34A automatic or manual?

The Seiko NH34A is an automatic (self-winding) movement: a rotor winds the mainspring from the motion of your wrist, so it needs no battery. It can also be wound by hand via the crown.

What is the power reserve of the Seiko NH34A?

About 40 hours on a full wind — into a second day, so it keeps running overnight off the wrist. Power reserve is how long the Seiko NH34A keeps running once you stop wearing or winding it.

Does the Seiko NH34A hack (stop the seconds when you set it)?

Yes. Pulling the crown stops the seconds hand, so the Seiko NH34A can be set precisely to a reference time before you push the crown back in. Hacking is what lets you sync several watches — or a watch and a phone — to the exact second.

Does the Seiko NH34A have a date function?

Yes — the Seiko NH34A can drive a date display, though whether a given watch actually shows the date depends on the dial the maker chose, so check the individual model rather than the movement.

Spotted something wrong? Report a correction →