Worn by Louis Cartier himself, the Tank Louis Cartier watch sets the standard to be upheld by all Tank watches. In contrast to the assertive choice of rectangular form and proud lines, the tops of the lugs were rounded, embodying the contribution made by Louis Cartier to the modern style later known as Art Deco. 18K yellow gold case, 18K yellow gold circular-grained crown set with a sapphire cabochon, mineral crystal, silver-grained dial, Roman numerals, sword-shaped blued-steel hands, alligator strap with 18K gold ardillon buckle, Cartier calibre 688 quartz movement, water resistant to 30 metres / 100 feet. Case dimensions: 33. 7 x 25. 5 mm, 6. 35 mm thickness.