Seiko 4502-7001
The 4502-7001 is a King Seiko Hi-Beat from Daini Seikosha, made from about 1968 into the early 1970s. The caseback reads 4502-7001 around a gold KS medallion carrying the Daini mark, and the hand-wound 4502A inside is signed 25 JEWELS. It runs at 36,000 bph, hacks, and has a date at 3. The dial reads KS and HI-BEAT over the Daini mark, with an applied SEIKO, a double index at 12, faceted applied batons and the dial code 4502-7000T AD at the bottom edge. The case is about 36.5mm with flat, sharp facets; rounded edges mean it has been polished. The caseback serial 140106 dates this example to April 1971, matching the caption.
| Caliber | 4502A |
|---|---|
| Years | 1968 to 1974 |
| Line | King Seiko |
| Function | Dress |
| Sub-line | Hi-Beat |
| Case size | 36.5mm |
| Factory | Daini |
What is the difference between the caliber 4500A and 4502A?
The 4500A shows the time only. The 4502A adds a date. Both are hand-wound 36,000 bph Daini movements, so check the caliber on the movement and the four-digit prefix on the caseback agree.
What should the case finish of a 4502-7001 look like?
Flat, brushed and polished planes meeting at sharp, unchamfered edges, the case style Seiko developed under Taro Tanaka. Soft or rounded edges mean it has been polished, which takes more value out of this reference than most wear.
What commonly happens to the caseback medallion on this reference?
The original gold KS medallion is highly vulnerable to degradation from sweat and moisture. It is common to find examples where the medallion is corroded, heavily worn, or entirely missing.
