In 2021, realising the Tank Solo had become about as thrilling as a tax return, Cartier quietly retired it to resurrect the Must in a modern, oversized avatar—Reference WSTA0040. It’s a brilliant piece of nostalgia marketing tailored specifically for those who crave a slice of Parisian heritage on their wrist, yet break into a cold sweat at the mere thought of hand-winding a vintage watch like it's 1917.
Softer Edges, Sharper Identity
Where the outgoing Tank Solo featured razor-sharp edges and slab sides rigid enough to slice cheese, the Must XL has finally embraced the sensual, rounded curves of the legendary Tank Louis Cartier. The vertical steel brancards framing the 31 x 41 mm case have been softened, allowing the watch to hug the wrist rather than sit atop it like a polished paving slab. At the center of the silvered dial, a radiant sunray guilloché square steals the spotlight, framed by commanding black Roman numerals and those signature blued-steel hands that effortlessly exude old-money charm.
The Secret Detail
Here is the obscure nugget of trivia to drop at dinner parties just to make fellow watch snobs feel painfully underinformed: beyond the famous microscopic "Cartier" signature hidden inside the VII numeral, almost nobody knows that tucked beneath that 8.37 mm thin case lies a stealth soft-iron Faraday cage. Cartier fitted the WSTA0040 with an internal anti-magnetic shield to protect the movement from modern smartphones and laptops—a rugged engineering detail worthy of a scientist's tool watch that the Maison almost snobbishly refrained from hyping up, lest it ruin the watch's delicate dress-party reputation.
A Mechanical Heart with a Practical Streak
Ticking away inside is the in-house Calibre 1847 MC—a nod to Cartier’s founding year in 1847—which delivers modern automatic reliability for people who love mechanical soul without vintage maintenance headaches. Adding to its everyday genius is the patented QuickSwitch system: a tiny mechanism hidden on the underside of the strap that lets you swap from alligator leather to a steel bracelet in under three seconds, saving your lugs from butchery by slip-prone springbar tools.
The Verdict for the Cocktail-Hour Intellectual
In a market flooded with 300-metre dive watches worn by people whose deepest aquatic adventure is a dip in the hotel pool, the Tank Must XL WSTA0040 is the ultimate flex of quiet sophistication. It glides under a tailored cuff with arrogant ease while looking remarkably sharp with a casual knit, proving you don't need a 44mm wrist-weight to command a room. It remains the thinking person's choice: timelessly elegant, mechanically clever, and satisfyingly distinct from the crowd.