SARB017 vs SPB121
The original Japan-market Alpinist and the Prospex Alpinist that replaced it.
The differences that matter
- Size: the SPB121 is 1.5 mm wider (39.5 vs 38 mm).
- Thickness: the SARB017 is slimmer (12 vs 13.2 mm).
- Movement: 6R15 in the SARB017 (hacks and hand-winds), 6R35 in the SPB121 (hacks and hand-winds); power reserve 50 vs 70 hours.
- Availability: neither is sold new by Seiko US any more, so both are mostly bought pre-owned.
Side by side
| SARB017 | SPB121 | |
|---|---|---|
| Price | Not sold new by Seiko US | $725 |
| Size | 38 mm × 12 mm | 39.5 mm × 13.2 mm |
| Strap width | — | — |
| Comes on | Leather strap | — |
| Water resistance | 200 m | 200 m |
| Sapphire crystal | Yes | Yes |
| Lume | Hands and markers | — |
| Screw-down crown | — | — |
| Movement | Automatic, hand-winding | Automatic, hand-winding |
| Bezel | Inner rotating compass ring | — |
| Hacking seconds | Yes | Yes |
| Hand-winding | Yes | Yes |
| Power reserve | About 50 hours | About 70 hours |
Figures come from each watch’s sources, listed on its own page.