Date hand indicator

Jaeger-LeCoultre Master Calendar Red Gold\\ with **date hand** (click to enlarge!)
Jaeger-LeCoultre Master Calendar Red Gold
with date hand
© Jaeger-LeCoultre

Compared with the fairly common digital date indication, the date hand indication (or pointer date) is the much rarer variant an analog indication, where a hand rotates around its axis once in 31 days and thus shows the date.