This is a vintage Cartier Must de Cartier Vermeil tank watch. It is the highly collectible manual wind version of this classic design. The dial of the watch is "lemon" color, the rarest of tank dials. The Hour indices are the iconic Roman numerals. 

The case measures 23.5mm x 30.5mm and is vermeil, solid sterling silver overlayed with 18K yellow gold. This watch has its original Cartier tang buckle.

The watch has been serviced and is running well. It will come with a one year warranty.