1910s Antique Swiss Unsigned 8-Day Pocket Watch with Alloy Case, in Good Working Condition

We would like to introduce you to a Swiss-made 8-day pocket watch.

This is a Swiss pocket watch believed to date from the 1910s.
There is no marking of the manufacturer's name or anything else, but the dial simply says "8 DAYS."
Many 8-day mechanical watches have a unique Hebdomas design, but this one has a similar design to a typical pocket watch of the time, and still maintains a solid 8-day power reserve.
It is unknown if it has been overhauled, but the balance wheel is in good condition and ticks along smoothly.

We hope this once-in-a-lifetime encounter will be a special one for you!

(Explanatory video)
I will add it later

【condition】
Appearance: ★★★★☆ Excellent condition with no noticeable scratches or stains

Function: ★★★★☆ Maintenance history unknown but in good working condition (within 5 minutes per day)

-Case: There is some wear over time, but there are no noticeable scratches and it is in good condition.
Case engraving: No engraving is visible
-Dial: There are small hairlines around 4 and 8 o'clock
Other: The windshield is made of mineral glass and has some small scratches.
Accuracy: Approximately 1 minute per day when measured with a flat timegrapher
Power reserve: 8 days from full spring

*The daily difference may vary depending on your posture, so please use this as a reference only.
*It is very old, so I don't know the history of parts replacement or repairs.

【detail】
Brand: Unknown *Made in Switzerland
・Year of manufacture: 1910s
Movement: Mechanical
・Mainspring: Manual winding
・Time setting: Pull out the crown (pendant set)
・Serial No. 40457
-Case material: Nickel alloy
・Case diameter 52mm (excluding crown)
・Case thickness 15mm (including crystal)
・Weight 103g

*This is an antique item and there is no other item that is exactly the same.
※If you have any questions, please feel free to ask.