Tap the image to enlarge
Bremont Supermarine S300/BR 40mm Automatic Mens Watch
Ref. S300-BK-B
The Supermarine line is Bremont's answer to a specific brief: a serious dive-rated watch built around the same exacting tolerances the brand applies to its aviation pieces. The S300 takes its name from its depth rating and is built around Bremont's Trip-Tick construction, in which the case barrel — here given a DLC treatment that accounts for the blacked-out mid-section — is machined as a separate component and torqued between the lugs. It is an unusual approach for a tool watch, and it gives the case a layered, purposeful look that sets it apart from a conventionally machined steel case. At 40mm it sits at the more wearable end of dive watches, and the ceramic bezel keeps weight in check while resisting the kind of surface scratching that catches on a fabric cuff. The COSC chronometer certification on the BE-92AE movement is not decorative; it means rate accuracy has been independently verified to standards that most movements sold at this kind of level are not held to. The screw-down caseback carries decorative finishing that the owner will see rarely, but it is there — a detail that suggests the watch was built to be opened and examined, not just worn.
- Reference
- S300-BK-B
- Brand
- Bremont
- Collection
- Supermarine
- Case size
- 40mm
- Case material
- Stainless steel
- Dial
- Black
- Crystal
- Sapphire
- Bezel
- Unidirectional rotating
- Movement
- Automatic
- Calibre
- BE-92AE
- Functions
- Date
- Water resistance
- 300m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Lume
- Super-LumiNova
- Condition
- Ex-display
- Retailer
- Goldsmiths
Additional specifications
- Power reserve
- 38 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 (3,006), Automatic Watches (1,368), Sports Watches (700), Dive Watches (484) and Pre-Owned, Ex-Display & Vintage Watches (154).
Manufacturer’s guarantee
What the specifications mean
A mechanical watch built to be worn hard and got wet.
Strengths
- 300m water resistance, rated for actual diving
- 40mm suits most wrists
- Sapphire crystal, which resists scratching
- Luminous hands and markers for low light
Worth knowing
- 38-hour reserve means winding it after a day off
Compare alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | S300-BK-B | L37644909 | YA136357 |
|---|---|---|---|
| Price | £2,775 | £2,850 | £2,040 |
| Case size | 40mm | 39mm | 40mm |
| Water resistance | 300m | 300m | 300m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Rubber strap | Stainless steel bracelet |
| Power reserve | 38 hours | 72 hours | 38 hours |
| This watch | Closely matched |
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 300m it is rated for swimming, snorkelling and recreational diving.
Will the glass scratch?
Unlikely. Sapphire is second only to diamond in hardness and shrugs off everyday marking.
Does it need a battery?
No. It is automatic — the motion of your wrist winds it, and there is no cell to replace.
How long does it run for when it's not worn?
About 38 hours fully wound — so it will usually stop if you leave it off overnight.
Is it a men's or women's watch?
Listed as men's, though at 40mm it sits in the range that suits anyone.
Cheapest place to buy
Goldsmiths at £2,775, ex-display. No UK retailer we track lists this reference new.
Is this available new?
Not from the UK retailers we track. This reference is listed as ex-display only, at £2,775 from Goldsmiths. Ex-display watches are unworn shop stock rather than second-hand — sold below the recommended retail price, and with the manufacturer’s guarantee intact.
Who are Goldsmiths?
Goldsmiths has been selling watches in Britain since 1778 and is part of the Watches of Switzerland Group, which is listed on the London Stock Exchange. They are an authorised dealer, so a watch comes with the manufacturer’s own warranty.
You may also like
In stock, and close on style and price
