Is your Tank Solo
the real deal?
The Cartier Tank Solo (now succeeded by the Tank Must) is one of the most recognizable rectangular dress watches ever made. Originally designed in 1917 and inspired by the track profile of WWI Renault tanks, the Tank's clean lines and elegant proportions have been endlessly counterfeited.
How to authenticate a Tank Solo
Case Shape & Proportions
The Tank Solo has a precise rectangular case with brancards — the vertical side bars — that extend to form the lugs. These proportions are specific and well-defined. The brancards should be flat (not rounded like the Tank Louis). Counterfeits often have slightly off proportions, with cases that are too wide, too narrow, or brancards that don't extend correctly.
Dial Details
The dial features a white or silver surface with Roman numeral hour markers in Cartier's distinctive typeface. Look for the printed "Cartier" signature, a railroad minute track around the perimeter, and blued steel sword-shaped hands. The printing should be crisp and the Roman numerals evenly spaced. Counterfeits often have incorrect fonts or poorly printed text.
Cabochon Crown
The crown features a genuine blue sapphire cabochon — a smooth, domed gemstone set into the winding crown. It should be richly colored with a deep blue hue, properly set flush into the crown, and feel smooth to the touch. Counterfeits often use glass or plastic that has bubbles, feels rough, or sits unevenly in the crown.
Case Back Engravings
The case back should feature a four-digit reference number, "Cartier" script in the correct typeface, a serial number, and a material stamp. All engravings should be deep, precise, and cleanly executed. Counterfeits often have shallow, poorly formed text with incorrect fonts or missing information.
Crystal
The Tank Solo uses a sapphire crystal with Cartier's secret signature — a tiny double-C logo laser-etched at 7 o'clock. This marking is nearly invisible to the naked eye but can be seen under magnification with a loupe. The crystal should be perfectly clear with no distortion. Counterfeits often use mineral glass and lack the secret signature entirely.
Strap & Deployant Buckle
The Tank Solo comes on genuine leather with a signed Cartier deployant or tang buckle. The leather should be high-quality with clean stitching and proper grain. The buckle should be engraved with "Cartier" in the correct typeface. Counterfeits often use low-quality leather with sloppy stitching and poorly engraved buckles.
Tank Solo counterfeit warning signs
Plastic or Glass Crystal Instead of Sapphire
Genuine Cartier watches use scratch-resistant sapphire crystal. If the crystal scratches easily, shows distortion, or feels warm to the touch (glass warms faster than sapphire), it's likely a counterfeit.
Painted or Glued-On Crown Stone
The sapphire cabochon should be a genuine polished gemstone properly set into the crown. If the stone appears painted on, is glued in place and sits unevenly, or lacks the characteristic deep blue color of sapphire, the watch is counterfeit.
Incorrect Roman Numeral Font or Spacing
Cartier uses a very specific Roman numeral typeface on the Tank dial. The numerals should be evenly spaced, perfectly symmetrical, and in the correct proportions. Any variation in font style, uneven spacing, or incorrect sizing is a strong indicator of a counterfeit.
Missing Secret Signature at 7 O'Clock on Crystal
Since the 1990s, Cartier has laser-engraved a tiny double-C monogram on the crystal at 7 o'clock. Use a loupe or magnifying glass to check. If this signature is missing, the watch is very likely counterfeit.
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Frequently asked questions
What is the difference between Tank Solo and Tank Must?
The Tank Must replaced the Tank Solo around 2021 with updated case sizing, SolarBeat solar-powered movement options, and new dial colors. The Solo used quartz movements. Both share the iconic Tank rectangular design.
How can I check the sapphire cabochon?
A genuine Cartier cabochon should be a polished, domed synthetic blue sapphire. It should feel smooth and be properly set flush into the crown. Fakes often use glass or plastic that feels rough, has bubbles, or sits unevenly.
What is the Cartier secret signature?
Since the 1990s, Cartier has laser-engraved a tiny double-C monogram on the crystal at 7 o'clock. It's nearly invisible to the naked eye but can be seen with a loupe or magnifying glass.