The Montblanc 1858 GMT, reference number 129615, features a 42 mm stainless steel case and a black sunray dial with Arabic numerals and index hour markers. It is powered by the automatic MB 24.33 movement, offering a 50-hour power reserve. The watch includes a unique GMT function displayed via a red square moving around the dial's perimeter, indicating a second time zone without an additional hand. Additional features include a date display and water resistance up to 100 meters. The timepiece is completed with a stainless steel bracelet and a folding clasp. The case back is engraved with a depiction of the continents, oceans, and city names representing the 24 time zones. Reference number: 129615.