朗格，精細，18k紅金腕錶，配月相、日曆顯示及動力儲存，“Grand Lange 1 Moon Phase”，約2004年製

The present model was introduced to the market in 2002, the Lange 1 Moonphase model features another technological advancement, a waxing and waning moon that never stands still as long as the watch is wound. While most moon phases click into position and don't move again until a certain segment of time has passed (typically one day), the Lange 1 Moonphase offers the most reliable depiction of moon time because it is always in motion.

The moonphase disc is connected to the continuum of the hour wheel and emulates the moon's orbit with a deviation of merely .002 percent. The new Lange 1 Moonphase errs by only 1.9 seconds per day, or 57 seconds per lunar orbit (a total of about 11 minutes per year), as compared to other moonphase watches whose inaccuracies result in approximately 44 minutes per year.