25800BA, Royal Oak Perpetual Calendar, Black Dial, Yellow Gold Brass a micro-rotor featuring the Louis-Cottier

a micro-rotor featuring the Louis-Cottier world time complication and (for the first time) romantic central moonphase display

A RN Chronomètre à Résonance

This gilt example is beautifully preserved with the sort of light

It has since become highly collected for its remarkably perfect design

also known as the Clint Eastwood

25800BA, Royal Oak Perpetual Calendar, Black Dial, Yellow Gold Brass a micro-rotor featuring the Louis-CottierA ref. 25800BA Royal Oak Perpetual Calendar with a black dial. The 25800 is one of the least seen Royal Oaks made from 1996 until 2002 in tiny numbers. It is a diminutive 33mm, to date the smallest Royal Oak Perpetual Calendar made and also the smallest perpetual calendar integrated bracelet sports watch yet made from any 'holy trinity' brand. Its calibre 2141 2806 was developed specifically for this reference alone. It is a category defying, quite