Winter poses a variety of issues for the watch wearer — useful, sartorial and sometimes complex issues. Similar to the ref. 6536 previously mentioned, it had been obtainable in either chronometer and non-chronometer variants, but this was The very first time the COSC watches essentially experienced the 'Formally Licensed Chronometer' https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/