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Citizen Promaster Diver 44mm Mens Watch - Stainless Steel
Ref. CA0820-50X
Sits in Citizen’s upper tier here — more premium than three quarters of the Citizen watches we list, which start at £139.
Price range £139 to £895 across 95 Citizen watches in stock.A 44mm stainless steel case, 13.8mm thick, houses a green dial fitted with luminous baton hour markers and luminous hands. The chronograph layout spreads across three sub-dials, measuring elapsed time to one-fifth of a second up to 60 minutes, with a 24-hour display and a date window at three o'clock. A green unidirectional rotating bezel completes the diving configuration, which meets ISO scuba standards to 200 metres. The screw-down crown and screwed caseback reinforce the water resistance rating. The Calibre B612 Eco-Drive movement runs on any light source and holds a charge for up to 210 days. It includes overcharge prevention and a low-charge warning. A stainless steel bracelet with a push-button folding clasp secures the watch to the wrist. The mineral crystal is rated impact and shatter resistant.
- Reference
- CA0820-50X
- Brand
- Citizen
- Collection
- Promaster
- Case size
- 44mm
- Case thickness
- 13.8mm
- Case material
- Stainless steel
- Case shape
- Round
- Dial
- Green
- Crystal
- Mineral
- Bezel
- Unidirectional rotating
- Movement
- Solar
- Calibre
- B612
- Functions
- Chronograph, Date, Solar powered
- Water resistance
- 200m
- Bracelet / strap
- Stainless steel bracelet
- Strap colour
- Silver
- Clasp
- Folding clasp
- Lume
- Luminous
- Retailer
- Goldsmiths
Learn more about Citizen
The Shokosha Watch Research Institute began in Tokyo in 1918, and the Citizen name was given to its first pocket watch in 1924 by the then mayor of Tokyo, Shinpei Goto, who wanted a watch that would be available to ordinary citizens rather than only the wealthy. The company formally took the name in 1930.
That founding intention has held. Citizen is the largest watch manufacturer in the world by volume and is fully vertically integrated, making its own movements, cases, and electronic components.
Its most significant technology is Eco-Drive, introduced in 1976 and refined over decades. A photovoltaic cell beneath the dial converts any light — including indoor light — into stored energy, so the watch never needs a battery change. Citizen has sold well over a hundred million Eco-Drive watches, and the environmental argument is substantial: hundreds of millions of cells not discarded.
The company also produced the first analogue quartz watch with a titanium case in 1970, the first professional dive watch with an electronic depth sensor, and the Caliber 0100, an Eco-Drive movement accurate to within one second a year — the most accurate independent watch movement ever put into production.
Citizen owns Bulova, Frederique Constant, Alpina, and the movement manufacturer Miyota, whose calibres power a large share of the affordable mechanical watch market worldwide.
- 1918
- The Shokosha Watch Research Institute is founded.
- 1924
- The Citizen name is given to its first pocket watch.
- 1976
- Eco-Drive light-powered technology is introduced.
- 2018
- The Caliber 0100 achieves accuracy of one second a year.
Also in 7 collections
This watch appears in the Citizen Promaster range (11), Back in Stock (3,616), Stainless Steel Watches (3,157), Chronograph Watches (1,205), Watches 44mm and Over (811), Sports Watches (793) and Dive Watches (566).
Temporarily out of stock
Goldsmiths is not currently taking orders for this reference. Last listed as available on 15 September 2026. Stock is checked nightly and this page updates when it returns.
What the specifications mean
A watch built to be worn hard and got wet.
Strengths
- 200m water resistance, rated for actual diving
- Luminous hands and markers for low light
- One of Citizen's more premium watches
Worth knowing
- 44mm sits at the larger end
Citizen Promaster Diver alternatives
Watches from other brands at a similar price, style and size, so you can see what else your budget can buy.
| Specification | CA0820-50X | GM-B2100D-1AER | RA-TX0207R10B |
|---|---|---|---|
| Price | £399 | £499 | £299 |
| Case size | 44mm | 44mm | 42.8mm |
| Water resistance | 200m | 200m | 200m |
| Movement | Solar | Solar | Solar |
| Strap | Stainless steel bracelet | Stainless steel bracelet | Stainless steel bracelet |
| This watch |
|
|
Your new watch
Frequently asked questions, and things you should know about this watch
Can I swim with it?
Yes. At 200m it is rated for swimming, snorkelling and recreational diving.
Water resistance explainedWill the glass scratch?
It can, over time. Mineral glass handles daily wear but will pick up fine scratches that sapphire would not.
Sapphire, mineral and acrylic comparedDoes it need a battery?
No. It charges from light, and the cell behind that is designed to last a decade or more.
Quartz, automatic and solar comparedIs it a men's or women's watch?
Listed as men's.
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