Seiko 4R16

Caliber 4R16 is an automatic movement manufactured by Seiko and part of the 4R family of in-house calibers. As an early iteration within the 4R line, it represents Seiko's entry-level automatic platform, positioned below the 6R series in the manufacturer's movement hierarchy. The movement features a hacking seconds mechanism and manual winding capability, characteristic of the 4R family's functional design. It was discontinued in favor of later 4R variants with updated specifications.