Photo by 663highland (CC BY 2.5), via Wikimedia Commons · Seiko Prospex Alpinist — same Alpinist line as the SPB121; older-generation reference (SARB017 ancestor) in this image, dial design closely matches the SPB121.
Seiko
Prospex Alpinist SPB121
Ref. SPB121J1
2020–present · 39.5mm · caliber 6R35
Recent comparable sales
Market value
Pending ingest
No comparable sales on file yet — the live comp ingest path ships when the data layer is wired (Q3). We don’t publish a fair-value range until real comps land.
Movement tier — unclassified
Not yet rated
Community + OSINT signals haven’t landed for this reference yet. We don’t publish a rating against zero signal — the number would mean nothing. Editorial body + caliber + market value still surface above; ratings appear once the signal corpus does.