The current reference of Arnold & Son, Instrument DBG Equation GMT, features two separate time displays, each driven by its own barrel and gear train with its own escapement and balance. This double barrel and escapement system permits the watch to be set independently to display two time zone, not only showing the hour difference, but also the minute difference when it comes to those time zones that differ from Greenwich Mean Time by a fraction of an hour, such as a quarter or a half. It houses an exclusive Arnold & Son mechanical movement A&S1209 and is available in either rose gold or steel.