CARTIER: AN 18K 'TANK AMÉRICAINE' WATCH, CIRCA 2015 The 4-jewel Cal-157 quartz movement, rectangular dial with black Roman numerals, black inner minute track with five minute markers, secret signature at 7, blued steel sword hands, brushed and polished gold case with back secured by 8 screws, blue sapphire faceted crown, brown leather strap with signed 18K gold buckle, dial, case and movement signed, with maker's mark, Swiss assay mark, European convention mark for gold, case no. 1450694X, ref. 2503, with certificate of authenticity dated March 2015, with maker's case and booklet, length 21.5cm, case 19mm