Epson · Japan
Epson VS42
The VS42 is Seiko Epson Corporation's solar-powered quartz caliber in the 11½-ligne (28.6 mm) round format, sold under the Epson or Hattori imprint. Technical documentation for the primary production variant, the VS42A, is dated August 4, 2023. The VS42A runs on a 32,768 Hz quartz oscillator and stores light-generated energy in a manganese titanium-lithium rechargeable capacitor (MT920), and is found in Lorus, Pulsar, and third-party OEM pieces.
The energy system uses a solar cell mounted beneath a semi-transparent dial to charge the capacitor. A full charge sustains approximately 12 months of operation in darkness, per Epson's own product listing. When voltage falls too low, the seconds hand shifts to two-second stepping to warn the wearer, and a quick-start feature starts the watch within seconds of exposure to light above roughly 1,000 lux, though the seconds hand initially moves at two-second intervals until sufficiently charged.
Designed for the value-to-mid segment of the market, the VS42 is a high-volume workhorse found in a wide range of everyday solar watches. Its slimness (3.5 mm including the capacitor), practical date complication, and maintenance-free power architecture make it well suited to casual dress and entry-level sports pieces. The two-jewel count and accuracy specification reflect its positioning as a utilitarian, volume-production caliber rather than a precision instrument.
Jewels
Reserve
In catalog
Technical specification
| Manufacturer | Epson |
| Origin | Japan |
| Type | Solar-quartz |
| Jewels | 2 |
| Power reserve | 8760 h |
| Diameter | 28.6 mm |
| Height | 3.5 mm |
| Hacking seconds | Yes |
| Hand-winding | No |
| Date | Yes |
| GMT | No |
| Chronograph | No |
| Accuracy (stated) | ±20 s/month |
1 model
Watches with this caliber
FAQ
Is the Epson VS42 automatic or manual?
The Epson VS42 is a solar quartz movement: a battery, kept charged by light, and a quartz oscillator keep time, so it is highly accurate and low-maintenance, with nothing to wind.
What is the power reserve of the Epson VS42?
On a full charge the Epson VS42 keeps running for about a year — its reserve here is stored charge, not a wound mainspring. It tops up from any light, so in normal wear it stays charged — there is nothing to wind and no battery to swap.
Does the Epson VS42 hack (stop the seconds when you set it)?
Yes. Pulling the crown stops the seconds hand, so the Epson VS42 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 Epson VS42 have a date function?
Yes — the Epson VS42 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.
How accurate is the Epson VS42?
The Epson VS42 is rated at ±20 s/month. That is typical of a quartz-regulated movement — far tighter than a standard mechanical watch, so you would only correct it a few times a year. Real-world accuracy still depends on how each watch is regulated, worn, and serviced.
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