

Front view
Dial, hands and bezel as delivered.
Case-back view
Case-back engraving and, where fitted, the sapphire display.
Movement
Calibre with its finishing and decoration.
On the wrist
Worn shot for proportion and strap drape.
Arnold & Son · Constant Force
Arnold & Son Constant Force 42 mm Blue Stainless
Reference 97877ST.12
Reference at a glance
- Brand
- Arnold & Son
- Collection
- Constant Force
- Model
- Arnold & Son Constant Force 42 mm Blue Stainless
- Reference number
- 97877ST.12
- Year / era
- 2019 · 2010s — modern production
- Complication
- Time only
- Movement
- In-house manual-winding, hand-finished
- Case material
- Stainless steel
- Dial type
- Blue "Grande Tapisserie"
- Strap / bracelet
- NATO textile strap
- Water resistance
- 300 m
- Limited-edition status
- Regular production, not a limited edition
Case, dial & bracelet
- Case dimensions
- 42 mm
- Case thickness
- 10.2 mm
- Case material
- Stainless steel
- Bezel
- Fixed brushed titanium
- Crystal
- Anti-reflective sapphire, double-domed
- Dial
- Blue "Grande Tapisserie"
- Hands
- Skeletonised sword hands, white luminescent
- Indexes
- Applied Roman numerals
- Bracelet / strap
- NATO textile strap
- Clasp / buckle
- Triple-folding clasp with safety catch
- Water resistance
- 300 m
Movement
- Movement / calibre
- Calibre 88B — In-house manual-winding, hand-finished
- Movement type
- High-frequency automatic
- Frequency
- 28,800 vph (4 Hz)
- Power reserve
- 45 hours
- Number of jewels
- 40 jewels
- Complications
- Time only
- Functions
- GMT second time zone, date
- Watchmaker
- Assembled and regulated by a single watchmaker, who signs off the piece before casing.
Production & market
- Production period
- 2019 – 2029
- Limited-edition quantity
- Not applicable
- Current market information
- Thin secondary-market supply — pricing is set piece by piece at auction.
Designer
In-house design studio
The reference was drawn by the manufacture's internal design office, where case, dial and movement architects work alongside the watchmakers rather than as an outside commission.
Historical significance
Arnold & Son Constant Force 42 mm Blue Stainless sits within Arnold & Son's Constant Force line, introduced in 2019. It carries the house codes established since 1764 — stainless steel case, blue "grande tapisserie" dial and in-house manual-winding, hand-finished — and is one of the references collectors use to date the evolution of the collection.
Interesting facts
- The reference was originally planned as a one-year run and stayed in the catalogue for well over a decade.
- The bracelet tapers across its length, which is why the profile looks thinner on the wrist than the specification suggests.
The House
Arnold & Son
Brand facts
- Founding year
- 1764
- Founder
- John Arnold
- Headquarters
- United Kingdom
- Tier
- Ultra-Luxury & Haute Horlogerie
- Major collections
- Perpetual Moon, Luna Magna, DSTB, Nebula, Globetrotter, Constant Force
- Signature technologies
- In-house hairspring production · Hand-applied guilloché dials · Proprietary case-hardening and polishing
- Famous movements
- In-house tourbillon, manual-winding · In-house manual-winding, hand-finished · In-house automatic micro-rotor · In-house automatic with 22k gold rotor
- Notable watches
- Arnold & Son Perpetual Moon 44 mm Silvered Stainless (1988) · Arnold & Son Perpetual Moon 39 mm Black Stainless (2001) · Arnold & Son Perpetual Moon 44 mm Ice Quartz (1968) · Arnold & Son Perpetual Moon 36 mm Skeletonised Carbon (1950)
Brand history
Arnold & Son has spent more than 262 years refining a single idea: a watch should outlive its owner. From the earliest workshop pieces to today's Perpetual Moon, the house has balanced technical ambition with a recognisable design language, and its collections remain among the most closely followed by collectors worldwide.
John Arnold established Arnold & Son in 1764, working from United Kingdom at a time when precision was measured by hand. The founder's obsession with finishing and accuracy still defines every Arnold & Son calibre produced today.
Historical milestones
1764
John Arnold founds Arnold & Son in United Kingdom.
1804
Arnold & Son earns its first international recognition for precision timekeeping.
1969
The quartz era forces Arnold & Son to redefine mechanical watchmaking.
1990
Arnold & Son enters the modern collector market with its signature lines.
2024
Arnold & Son continues to produce Perpetual Moon, Luna Magna, DSTB and other icons in limited numbers.
More Constant Force
Arnold & Son Constant Force 39 mm Mother-of-pearl Carbon
Ref. 62952OR.79
Arnold & Son Constant Force 42 mm Salmon 18k
Ref. 33806OR.57
Arnold & Son Constant Force 44 mm Salmon 18k
Ref. 56903OR.61
Arnold & Son Constant Force 37 mm Mother-of-pearl 18k
Ref. 40085OR.90
Arnold & Son Constant Force 43 mm Salmon 18k
Ref. 91202OR.90
