Seiko 6R15 caliber vs Seiko 7S26 caliber: specs compared
Updated 05 September 2026.
6
specs differ
Seiko 6R15 caliber and Seiko 7S26 caliber differ on 6 specs: movement height, jewels, winding, calendar / layout, stem, power reserve.
| Spec | Seiko 6R15 caliber | Seiko 7S26 caliber |
|---|---|---|
| Maker | Seiko | Seiko |
| Size | 12 ligne | 12 ligne |
| Casing diameter | 27.40 mm | 27.40 mm |
| Movement height | 5.25 mm | 4.90 mm |
| Frequency | 21,600 A/h (3 Hz) | 21,600 A/h (3 Hz) |
| Jewels | 23 | 21 |
| Winding | automatic, bidirectional, hacking and hand-wind | automatic, unidirectional, no hand-wind or hack |
| Calendar / layout | centre seconds, date at 3 | centre seconds, day and date at 3 |
| Hand fitting | hour 1.50 / minute 0.90 / second 0.20 mm (bore) | hour 1.50 / minute 0.90 / second 0.20 mm (bore) |
| Stem | 6R15 stem | 7S26 stem |
| Power reserve | approx. 50 h | approx. 41 h |
Questions and answers
How do Seiko 6R15 caliber and Seiko 7S26 caliber compare?
Seiko 6R15 caliber and Seiko 7S26 caliber differ on 6 specs: movement height, jewels, winding, calendar / layout, stem, power reserve.