Winter poses quite a few issues for the watch wearer — sensible, sartorial and at times technological concerns. Similar to the ref. 6536 higher than, it was available in possibly chronometer and non-chronometer variants, but this was The 1st time the COSC watches actually experienced the 'Formally Qualified Chronometer' text https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/