Cartier brought the Tank Must back in 2021 as a broader Tank collection, not a line made entirely of solar watches. Its notable technical debut was SolarBeat: a photovoltaic quartz movement that gathers light through tiny openings in the dial. The collection also included conventional quartz and automatic options, alongside new dial colors and strap choices.
What Cartier brought back in 2021
The Tank Must’s return was a collection story. Launch coverage described small, medium, and large watches with quartz and automatic movements. It also reported monochrome red, blue, and green versions, plus SolarBeat models and non-animal straps planned to expand the range in September 2021. Those details describe the 2021 lineup and rollout, not every configuration available today. OPENERS’ Watches & Wonders 2021 launch coverage reported selected steel models’ specifications and tax-inclusive prices for Japan; those were historical Japan-market figures, not current or worldwide prices.
What is the Cartier Tank Must SolarBeat?
SolarBeat is a photovoltaic quartz watch: light powers its rechargeable battery through a photovoltaic cell beneath the dial. Cartier’s 2021 announcement called it the first Cartier watch to benefit from this movement and said the watchmaking workshop’s research team spent two years developing it. The tiny perforations in the Roman numeral markers let light pass through the dial to the cell. Cartier’s announcement described the SolarBeat launch and its strap; Cartier’s Tank Must SolarBeat user guide explains the charging mechanism.
How SolarBeat charges and how long it runs
Cartier says the battery recharges in daylight or artificial light, with charging speed dependent on the light exposure. The guide estimates about five months of autonomy when fully charged and advises frequent light exposure for better efficiency and normal battery behavior. Cartier also publishes an estimate of at least 16 years without battery replacement, compared with eight years for its high-autonomy quartz and three years for classic quartz. These are Cartier’s figures, not independently verified test results.
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- Automatic Mechanical Movement: Manufactured with self-winding feature
- Movement Caliber: 1847 MC
- Case Material: Steel, Crown with Synthetic Spinel
- Dial & Hands: Silvered Flinque Dial, Blued-Steel Sword-Shaped Hands
- Strap & Buckle: Interchangeable Black Calfskin Strap, Steel Deployant Buckle
How the 2021 Tank Must options differed
| Option | Movement or feature | What to know |
|---|---|---|
| SolarBeat | Photovoltaic quartz | Light reaches a cell through perforations in the dial; this is one Tank Must option, not a feature of the entire collection. |
| Other quartz | Quartz | Included in the broader 2021 assortment; these watches are distinct from photovoltaic SolarBeat models. |
| Automatic | Automatic | Also reported among 2021 options; it is not a SolarBeat configuration. |
| Monochrome editions | Movement not specified in the cited 2021 coverage | Red, blue, and green dial versions were reported as additions to the range. |
The 2021 launch coverage described small, medium, and large sizes. Current Cartier listings cited here show small and large SolarBeat examples, but they do not establish the full present-day collection or reproduce the complete 2021 roster.
SolarBeat’s strap and current listed configurations
Cartier’s April 2021 announcement described a non-animal strap containing about 40% plant-based material, made using apple waste from food-processing industries in Switzerland, Germany, and Italy. This is the brand’s description of the material, not an independent composition assessment.
Rank #2
- Imported
- Pre-Loved Condition: Excellent; Faint signs of wear.
- Case Size/Width: 20mm, Watch Height: 6mm, Band Width: 15mm, Wrist circumference: 5.5"
- Band material: Stainless Steel
- Case material: Stainless Steel
Current Cartier pages show small SolarBeat watches measuring 29.5 × 22 mm and large examples measuring 33.7 × 25.5 mm. The listed configurations include calfskin straps and steel bracelets, and the cited listings specify water resistance up to 3 bar. These are current product-page details and may vary by market; they should not be read as a definitive inventory of 2021 launch versions. See Cartier’s listings for the small SolarBeat, large SolarBeat, bracelet configuration, and additional SolarBeat listing.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Why the return mattered
The Tank Must’s 2021 comeback combined familiar Tank styling with a wider spread of movements, colors, and configurations. SolarBeat stood out because it brought photovoltaic power into the collection without making solar charging a requirement for every Tank Must. Its perforated Roman-numeral dial is both a design detail and part of the mechanism: the openings provide a path for light to reach the cell below.
Quick Recap
Best Value
- Fit wrists size from 5 to 8 inches
- Selected high-grade silica gel, soft and odorless, smooth and non-scratching
- Package Included: Kevisae rubber watch band strap for 20mm cartier watch with silver buckle, free spring bar removal tool
- Please confirm the size of your watch interface before placing an order to avoid buying the wrong size strap
- Please feel free to contact us,if you have any questions,we will solve it as soon as possible
Rank #4
- PREMIUM MATERIAL: Our strictly selected high quality durable silicone rubber and 304 stainless steel to make these watch bands. They are soft and comfortable, sweat and water resistant, lightweight and easy to dry, flexible yet fairly sturdy. Perfect for your any type of workout or daily use.
- COMPATIBILITY: The flexible replacement watch band is Compatible with Cartier watch Must 21 Chronoscaph Autoscaph series W10125U2, W10147U2, W10184U2, W10197U2, W10198U2.
- OPTIMAL FIT AND EASILY SWAP: Adjustable length design, the watch strap Length 115mm+95mm (counting the length of buckle), size can be adjusted according to the circumstance of individual wrist. Fits wrist circumferences ranging from 5" to 8" (127mm-203mm). Specialty tool is also supplied to assist you in removing your old band, which lock your watch precisely and securely.
- WHAT YOU GET: 1 Watch Band, 1 Spring Bar Remover Tool, 2 Screwdriver Tool.
- CUSTOMER SERVICE: Your satisfaction and the establishment of reputation are our pursuit. If you have any questions or concerns, please feel free to contact us. We will reply to you within a short period of time.
Rank #3
- Cartier Baignoire Mini Model Silver Dial Watch WGBA0041
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
