Omega's Quartz movements are designed to continue to keep time with amazing precision, often dropping or attaining only some seconds per 30 days. Montblanc’s master craftsmen work diligently to build an Extraordinary array of timepieces in various models, within the chopping-edge amazing of your Timewalker collection for the ultra-deluxe Summit. https://www.watchesworld.com/a-history-of-watch-reference-numbers/