Wristwatch: very rare 18K pink gold Rolex 'Bubble Back' with special case, from the 40': Ca. Ø32mm, 18K pink gold, unusual and very rare special case, back screwed to the movement plate, serial number 473992, automatic chronometer, centre seconds, movement number 36170, very beautiful dial with Arabic numerals, luminous hands, black leather strap, intact, rare.