Family treeGrand Seiko 9R66 — Heritage family: 3 calibers, 2 sourced lineage links.Drag to explore.

100%drag to pan · hover a caliber to isolate its line · scroll the page normallyopen the full family view →

accepteddisputed

Sense of “family”Heritage · 3Everything (debug) · 3 Parts cluster (Jules Borel sense) · 1 Manufacturer-internal (Ranfft sense) · 1 Based-on star (WatchBase sense) · 3 Open the full family view →

movement

Grand Seiko 9R66

Grand Seikointroduced 2006design:grand-seiko-9r66compare specs · 3

bounding evidence — no range is drawn on the era axis

not before 1999

Seiko 7R68 · introduced 1999 (sourced)you cannot derive from what does not exist · ← derived from · ← derived from · rule IR-2 · depth 2 · acceptedthe anchor's own source

not before 2004

Grand Seiko 9R65 · introduced 2004 (sourced)you cannot derive from what does not exist · ← derived from · rule IR-2 · depth 1 · acceptedthe anchor's own source

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

Grand Seiko 9R66

movementproducer: Grand Seiko

IIDesignations — 0 names

No designation is recorded for this design yet.

IIIExecutions — 3 articles

No source in this corpus states which grade any Grand Seiko 9R66 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.

unknown

evidence: maker datasheetmodified by Grand Seiko9R16decoration Grand Seiko lion in 18K gold on the oscillating weight — the visible marker of the selected-oscillator rung.

Tolerances for this caliber at this grade

Measured: worn claim
Mean rate, centre: 0 s/d
Mean rate, tolerance: ± 1 s/d
Power reserve, typical: 72 h
Sampling: unknown

These figures belong to this caliber at this grade, and to nothing else. The same grade name on another caliber from the same maker carries different numbers.

exec:grand-seiko-9r66/9r16

unknown

evidence: maker datasheetmodified by Grand Seiko9R66

Tolerances for this caliber at this grade

Measured: worn claim
Mean rate, centre: 0 s/d
Mean rate, tolerance: ± 1 s/d
Power reserve, typical: 72 h
Sampling: unknown

These figures belong to this caliber at this grade, and to nothing else. The same grade name on another caliber from the same maker carries different numbers.

exec:grand-seiko-9r66/base

unknownsynthetic

evidence: unknown

Tolerances for this caliber at this grade

Measured: worn claim
Mean rate, centre: 0 s/d
Mean rate, tolerance: ± 1 s/d
Power reserve, typical: 72 h
Sampling: unknown

These figures belong to this caliber at this grade, and to nothing else. The same grade name on another caliber from the same maker carries different numbers.

no source states which grade this article was bought at — this row exists so 'unknown' stays countable instead of becoming an assumption

exec:grand-seiko-9r66/unknown

Specifications

Property	Value	Scope	Status
Jewels build.jewel_count	30	—	accepted
Date disp.has_date	yes	—	accepted
GMT hand disp.has_gmt_hand	yes	—	accepted
Power-reserve indicator disp.has_power_reserve_indicator	yes	—	accepted
Escapement family esc.family	none	—	accepted
Oscillator architecture osc.architecture	quartz_crystal	—	accepted
Power reserve (typical) power.reserve_typical_h	72 h	—	accepted
Introduced prod.intro_year	2006	—	accepted
Caliber supply type prod.supply_type	in_house	—	accepted
Quartz oscillator frequency qz.oscillator_frequency_hz	32768 Hz	—	accepted
Power source qz.power_source	mainspring	—	accepted
Regulator class qz.regulator_class	glide_wheel_em_brake	—	accepted
Movement technology qz.technology	spring_drive	—	accepted
Thermocompensated qz.thermocompensated	unknown	—	accepted
Hacking seconds wind.has_hacking_seconds	yes	—	accepted
Winding mode wind.mode	automatic	—	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 · 2

Where this construction came from. Read up the arrows.

Grand Seiko 9R65
derived from
Seiko 7R68
derived fromdepth 2

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.

Used by

models

brands

grade unknown

grain 26 reference — every record here sits at the same level, so the count is one kind of thing.

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

1
grand-seiko.com
https://www.grand-seiko.com/us-en/collections/movement/springdrive
manufacturertier 1retrieved 2026-08-2411 facts on this page
2
grand-seiko.com
https://www.grand-seiko.com/us-en/collections/movement/springdrive/9r66
manufacturertier 1retrieved 2026-08-2412 facts on this page
3
grand-seiko.com
https://www.grand-seiko.com/us-en/collections/movement/springdrive/9r65
manufacturertier 1retrieved 2026-08-242 facts on this page
4
Monochrome Watches
https://monochrome-watches.com/a-technical-perspective-defining-and-understanding-hybrid-watches/
presstier 2retrieved 2026-08-243 facts on this page