Seiko VS42A

The Seiko caliber VS42A is a solar-powered quartz movement manufactured in Japan. It draws power from a rechargeable capacitor (MT920) that stores energy converted from light passing through the dial, which requires at least 30% transparency. When fully charged, the movement runs for approximately six months with an accuracy of ±20 seconds per month. The movement contains two jewels and is also known as the V157 or V157A.