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Seiko › Field › Prospex › SPB121

Seiko SPB121

Prospex · Alpinist. No longer sold new by Seiko US

Video reviews

A Complete Package For Around $700 - Seiko Alpinist SPB121
Teddy Baldassarre · YouTube
Seiko Alpinist SPB121 (Exquisite Timepieces)
Random Rob · YouTube

Videos are made by independent reviewers and play from YouTube; they’re not ours. We picked ones that name this reference. Own one? Share your photos.

Where to buy

New · authorized

No longer sold new by Seiko in the US.

No seller listed for this one yet.

New · grey market (unauthorized)

Often cheaper. Covered by the store’s own warranty, not Seiko’s.

Pre-owned

The main way to buy this one now. Check condition, box and papers.

Search links show live listings, so check the exact reference before you buy. Prices change; each one shows when we checked it. We may earn a commission from some links. It doesn’t change your price or which stores we list. Authorized vs grey market vs pre-owned.

The basics

Price
$725
2020 launch, on strap
Size
39.5 mm × 13.2 mm
Water resistance
200 m
Sapphire crystal
Yes

How it works day to day

Movement
Automatic, hand-winding
Caliber 6R35, rated +25 to -15 s/day
Hacking seconds
Yes
Seconds hand stops when you pull the crown, so you can set the time exactly
Hand-winding
Yes
Power reserve
About 70 hours

Similar watches

SPB143
Prospex
40.5 mm · sapphire · 200 m
SPB155
Prospex
38 mm · sapphire · 200 m
SPB317
Prospex
41 mm · sapphire · 200 m
SARB017
SARB (Japan market)
38 mm · sapphire · 200 m

Compare

SARB017 vs SPB121: The original Japan-market Alpinist and the Prospex Alpinist that replaced it.

SPB121 vs SPB155: Two Prospex field watches on the same 6R35 movement.

Sources