Tap the image to enlarge
Hamilton Jazzmaster Open Heart Auto 42mm Unisex Watch Green
Ref. H32705160
Sits in Hamilton’s upper tier here — more premium than three quarters of the Hamilton watches we list, which start at £375.
Price range £375 to £2,265 across 72 Hamilton watches in stock.The Jazzmaster line has always sat at the dressier end of Hamilton's range — built for the wrist rather than any particular occupation, and drawing on the brand's long habit of making movements worth looking at. The Open Heart takes that instinct literally: the dial is cut away at centre to show the balance wheel turning, and on this version the surrounding green is a sunray gradient that draws the eye inward, darkening as it approaches the aperture. The H-10 inside is an ETA 2824-2 derivative, but the meaningful modification is the Nivachron balance spring — an alloy that resists both magnetic fields and temperature swings better than traditional steel, so the rate holds more consistently across a working day. The 80-hour reserve means a watch left on the nightstand Friday evening will still be running Monday morning. At 42mm with dauphine hands and luminous stick markers, it reads cleanly at a glance without the aperture becoming a distraction — the movement is visible without being the only thing visible.
- Reference
- H32705160
- Brand
- Hamilton
- Collection
- Jazzmaster
- Case size
- 42mm
- Case thickness
- 11.4mm
- Lug width
- 22mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Green
- Crystal
- Sapphire
- Movement
- Automatic
- Calibre
- ETA C07.611
- Functions
- Skeleton dial
- Water resistance
- 50m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Butterfly clasp
- Lume
- Luminous
- Retailer
- Goldsmiths
Additional specifications
- Lug-to-lug
- 50mm
- Power reserve
- 80 hours
Learn more about Hamilton
Hamilton was founded in Lancaster, Pennsylvania in 1892, and its early business was the railroad. American rail accidents caused by unsynchronised timekeeping had forced the industry to adopt strict standards, and Hamilton built pocket watches accurate enough to meet them — earning the description the watch of railroad accuracy.
Two things then defined it. The first was war: Hamilton supplied over a million watches to American forces in the Second World War, suspending civilian production entirely, and its marine chronometers were fitted across the US Navy.
The second was electricity. The Ventura of 1957 was the first battery-powered electric wristwatch, and its asymmetric shield-shaped case, designed by Richard Arbib, looked like nothing before it. Elvis Presley wore one in Blue Hawaii.
Hamilton's cinematic presence is unusually deep — over five hundred films — and includes the watches designed for 2001: A Space Odyssey with Stanley Kubrick, and appearances in Interstellar and Tenet.
American manufacturing ended in 1969 as the quartz crisis approached. The brand was acquired by the Swiss and is now part of the Swatch Group, based in Biel, where it occupies a distinctive position: American design heritage, Swiss production, and ETA movements with long power reserves at accessible prices. The Khaki Field, descended from the wartime issue watches, is its best-known line.
- 1892
- Founded in Lancaster, Pennsylvania.
- 1918
- Supplies the first US airmail flights.
- 1957
- The Ventura is the first electric wristwatch.
- 1968
- Designs the watches for 2001: A Space Odyssey.
- 1974
- Becomes Swiss-owned; now part of the Swatch Group.
Also in 6 collections
This watch appears in the Hamilton Jazzmaster range (16), Back in Stock (4,007), Stainless Steel Watches (2,833), Automatic Watches (1,417), Green Dial Watches (392) and Skeleton Watches (260).
Best of 2 retailers
What the specifications mean
A mechanical watch for everyday wear.
Strengths
- Sapphire crystal, which resists scratching
- 80-hour reserve survives a weekend off the wrist
- Luminous hands and markers for low light
- One of Hamilton's more premium watches
Worth knowing
- 50m suits rain and handwashing, not swimming
Hamilton Jazzmaster Open Heart Auto alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | H32705160 | FC-303NS5B6 | T1394071109100 |
|---|---|---|---|
| Price | £1,065 | £1,095 | £800 |
| Case size | 42mm | 40mm | 42mm |
| Water resistance | 50m | 50m | 50m |
| Movement | Automatic | Automatic | Automatic |
| Strap | Stainless steel bracelet | Leather strap | Stainless steel bracelet |
| Power reserve | 80 hours | 38 hours | — |
| This watch |
|
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Showering yes, swimming no. 50m covers splashes and brief immersion, but a swimming stroke generates well above the pressure that figure describes.
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 80 hours fully wound — enough to sit off the wrist over a weekend and still be running.
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.
Will it fit my wrist?
Lug-to-lug is 50mm, which suits wrists from roughly 16.5cm (6½ inches) upward.
Lug-to-lug decides fit more than case diameter does.
How to size a watch to your wristIs it a men's or women's watch?
Listed as unisex, and at this size it suits any wrist that takes the dimensions.
Cheapest place to buy
Both Mappin & Webb and Goldsmiths list it at £1,065, so choose on delivery and warranty rather than price.
More Hamilton watches like the Jazzmaster Open Heart Auto
In stock, and close on style and price
