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Bremont Altitude Chronograph GMT 42mm Mens Watch Black
Ref. ALT42-CHR-G-SS-BK-B
Sits in Bremont’s upper tier here — more premium than three quarters of the Bremont watches we list, which start at £2,895.
Price range £2,895 to £15,750 across 27 Bremont watches in stock.The Altitude line traces its roots to Bremont's work with Martin-Baker, the ejection seat manufacturer, and the Chronograph GMT represents its most complex iteration yet — stacking a chronograph and an independent GMT hand on top of the core aviation brief. The Trip-Tick case construction is retained: a three-piece architecture with a black DLC-coated knurled centre barrel sitting between the polished and brushed steel sections, a combination that does more for grip and identity than a plain case could. Inside, the BC781AC is chronometer-certified to ISO 3159, runs at 4Hz with a 62-hour reserve, and is isolated from the chassis by a rubber ring, with a soft-iron Faraday ring around the movement preserving anti-magnetic protection through the exhibition caseback. On the dial, the GMT hand is red-tipped against a 24-hour scale, so day and night read at a glance in a second zone, and the running seconds subdial is styled as a tri-blade propeller — a reference to a specific military project rather than decoration for its own sake. At 88.8 grams on the 904L H-link bracelet, it sits with some presence, though the curved bars and screw-pin link adjustment mean the fit can be dialled in precisely. Quick-release lugs make a strap swap straightforward without tools, which matters for a watch genuinely built to move between environments.
- Reference
- ALT42-CHR-G-SS-BK-B
- Brand
- Bremont
- Collection
- Altitude
- Case size
- 42mm
- Case thickness
- 14.7mm
- Lug width
- 22mm
- Case material
- Black PVD
- Case shape
- Round
- Dial
- Black
- Crystal
- Sapphire
- Movement
- Automatic
- Calibre
- BC781AC
- Functions
- Chronograph, GMT, Date, Small seconds, Skeleton dial
- Water resistance
- 100m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Deployant clasp
- Lume
- Luminous
- Retailer
- Mappin & Webb
Additional specifications
- Power reserve
- 62 hours
Learn more about Bremont
Nick and Giles English founded Bremont in 2002, four years after their father died in a plane crash that Nick survived. All three had restored and flown vintage aircraft together, and the brand that emerged is inseparable from that. The name comes from Antoine Bremont, a French farmer who sheltered the brothers after an emergency landing.
Bremont set out to rebuild British watchmaking, which had effectively ended in the twentieth century. The early watches used Swiss movements in British-designed cases, with the Trip-Tick three-part case construction and a hardened outer barrel treated to over 2000 Vickers.
The military and aviation work is real rather than thematic. Bremont holds contracts with squadrons across the RAF, the US Air Force, and other services, producing issued watches for specific units, and has made watches for Martin-Baker ejection seat survivors — tested to the ejection forces themselves.
The company has also built watches incorporating material from historical objects: oak and copper from HMS Victory, aluminium from the Wright Flyer, and steel from Bletchley Park.
The manufacturing ambition advanced with the opening of a facility in Henley and the release of the ENG300 series in 2021, the first Bremont movement designed and largely made in England. Production is in the low tens of thousands annually.
- 2002
- Nick and Giles English found Bremont.
- 2007
- The first watches ship with the Trip-Tick case.
- 2009
- The Martin-Baker collaboration begins.
- 2021
- The ENG300 becomes the first English-made Bremont calibre.
Also in 5 collections
This watch appears in Stainless Steel Watches (2,652), Automatic Watches (1,503), Chronograph Watches (990), Skeleton Watches (258) and GMT Watches (204).
What the specifications mean
A mechanical watch for everyday wear.
Strengths
- 100m water resistance covers swimming and watersports
- Sapphire crystal, which resists scratching
- Luminous hands and markers for low light
- Second time zone for travelling
- One of Bremont's more premium watches
Worth knowing
- 14.7mm thick, so it will not disappear under a cuff
Bremont Altitude alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | ALT42-CHR-G-SS-BK-B | CBN201C.FC6542 | L38215532 |
|---|---|---|---|
| Price | £5,750 | £5,700 | £5,900 |
| Case size | 42mm | 42mm | 42mm |
| Water resistance | 100m | 100m | 100m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Leather strap | Leather strap |
| Power reserve | 62 hours | 80 hours | 68 hours |
| This watch | Closely matched | Closely matched |
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 100m it is rated for swimming and snorkelling, though not for diving.
Water resistance explainedWill the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
Quartz, automatic and solar comparedHow long does it run for when it's not worn?
About 62 hours fully wound — enough to survive a night off the wrist, but not a full weekend.
What size strap does it take?
22mm. Any strap of that width will fit, and on most modern watches quick-release bars make the swap a two-minute job with no tools.
Is it a men's or women's watch?
Listed as men's.
Cheapest place to buy
Mappin & Webb is the only UK retailer we track stocking this reference, so there is nothing to compare it against today.
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