Rolex, Rare Gold Monopulsante Chronograph, Ref. 2021, circa 1930's Case: 39 mm, 18k yellow gold, hinged case back, signed "Rolex 27 Records Universels Geneve-Suisse", single olive-shaped push button, 13372 Dial: original silver dial, outer red telemeter scale, inner red tachymeter scale, black Arabic numerals, all original blued steel hands, Breguet moon hour and minute hands Movement: Rolex signed manual wind 17 rubies nickel movement, Cal. 14''', lever escapement Band: leather, plated buckle Signed: Rolex on the case and movement Reference 2021 is one of Rolex's earliest chronograph models, first launched in the 1920s, featuring a hinged caseback and an olive-shaped chronograph pusher. It is impressive in size at 39 mm diameter and has a rare original dial with red telemeter and tachymeter scales and original blued steel hands. HID03101062020 © 2020 Heritage Auctions | All Rights Reserved