Seiko J13046
The Seiko Cronos J13046 is a 35mm hand-wound watch from the early 1960s, produced by Daini Seikosha. Positioned as one of Seiko's earliest water-resistant models, it features a two-part caseback system that secured a 50-meter depth rating. This was a critical step in Seiko's development of waterproof cases, preceding their true dive models like the 62MAS. The dial displays a prominent "Water 50 Proof" designation, and the caseback is engraved with the seahorse emblem, which Seiko used to signify manual-wind waterproof capability. The watch is powered by a 21-jewel movement and is housed in a stainless steel case.
| Line | Cronos |
|---|---|
| Case size | 35mm |
| Lug width | 18mm |
| Crystal | Acrylic |
| Water resistance | 50m |
| Factory | Daini |
What does the seahorse on the caseback mean?
Seiko used the seahorse emblem during this era to denote manual-wind watches with water resistance. Automatic models typically received a dolphin engraving instead.
Is the Cronos J13046 a dive watch?
While collectors sometimes refer to it as a "pre-diver," the J13046 was rated to 50 meters and lacks a rotating bezel. It was designed for active everyday use like swimming rather than scuba diving, preceding Seiko's first true dive watch, the 62MAS.
