unknownsynthetic
evidence: unknown
no source states which grade this article was bought at — this row exists so 'unknown' stays countable instead of becoming an assumption
exec:zenith-el-primero-3620/unknown
accepteddisputed
movement
Zenith El Primero 3620
⟨2019 or later⟩ range only — no source gives an introduction yearderived from dated relatives · accepted
not before 2019
Zenith El Primero 3600 · introduced 2019 (sourced)
not before 1987
Zenith El Primero 400 · introduced 1987 (sourced)
Identity
A caliber is three separate things and this reference keeps them apart: the construction, the names it is sold under, and the article a brand actually bought. A watch model points at an execution — never at a bare construction — which is why “same caliber” is almost never a complete answer.
IDesign — the construction
Zenith El Primero 3620
movementproducer: Zenith
IIDesignations — 0 names
No designation is recorded for this design yet.
IIIExecutions — 1 article
No source in this corpus states which grade any Zenith El Primero 3620 was bought at. That unknown is stored as a real row rather than left blank, so it can be counted, filtered and excluded from any comparison that would otherwise assume parity.
Specifications
| Property | Value | Scope | Status | Sources |
|---|---|---|---|---|
Jewels build.jewel_count | 26 | — | accepted | |
Swiss movement origin.swiss_movement | yes | — | accepted | |
Frequency osc.frequency_vph | 36000 vph | — | accepted | |
Power reserve (typical) power.reserve_typical_h | 60 h | — | accepted | |
Winding direction wind.direction | bidirectional | — | accepted |
Lineage
The same relationships as the tree at the top of this page, with their sources. An absence in a column means no source stated one.
Ancestors · 3
Where this construction came from. Read up the arrows.
- Zenith El Primero 3600derived from
- Zenith El Primero 400derived fromdepth 2
- Zenith 3019 PHC (El Primero)derived fromrevision ofdepth 3
Descendants · 0
What came from it — revisions, variants, clones, licensed copies.
None recorded. An absence here means no source stated one, not that none exists.
Related · 0
Stored in a different table from descent. A successor is not a child.
None recorded. An absence here means no source stated one, not that none exists.
Curated family labels
El Primero (Zenith)
authority: zenith7 members
Used by
18
models
1
brands
18
grade unknown
grain 2 model · 16 reference — the count above mixes levels. A family record is one the source states a movement for family-wide; a reference record is one case reference. They are not the same unit and are never summed silently.
- Zenith18 modelsmodel:zenith/03-4000-3620-21-i001model:zenith/03-4000-3620-51-i003model:zenith/03-9300-3620-01-i001model:zenith/03-9300-3620-02-i001model:zenith/03-9300-3620-15-i001model:zenith/03-9300-3620-21-i001model:zenith/03-9300-3620-51-i001model:zenith/03-9301-3620-18-i001model:zenith/03-9302-3620-75-i001model:zenith/03-9303-3620-07-i001model:zenith/16-9300-3620-51-i001model:zenith/49-4000-3620-21-i001model:zenith/49-4001-3620-63-i001model:zenith/49-9300-3620-21-i001model:zenith/49-9308-3620-56-i001model:zenith/97-9300-3620-79-i001model:zenith/chronomaster-originalmodel:zenith/chronomaster-sport
Every brand here is on the strength of a source that names a watch and states this movement. Brands that use this caliber and nobody has sourced yet are absent — this is what has been researched, not what exists.
Sources
- 1Monochrome Watcheshttps://monochrome-watches.com/in-depth-the-history-of-the-zenith-el-primero-high-frequency-automatic-chronograph/presstier 2retrieved 2026-08-249 facts on this page
- 2Caliber Cornerhttps://calibercorner.com/zenith-el-primero-caliber-3620curated dbtier 2retrieved 2026-09-084 facts on this pagecited, never crawled
- 3zenith-watches.comhttps://www.zenith-watches.com/en_us/product/defy-extreme-97-9100-9004-80-i209manufacturertier 1retrieved 2026-08-241 fact on this page
- 4Monochrome Watcheshttps://monochrome-watches.com/zenith-chronomaster-2-the-next-big-step-forward-for-the-el-primero/presstier 2retrieved 2026-08-242 facts on this page
- 5Monochrome Watcheshttps://monochrome-watches.com/history-rolex-daytona-chronograph-1963-in-depth-review/presstier 2retrieved 2026-08-241 fact on this page