A RARE LARGE SIZED GENTLEMAN'S STAINLESS STEEL HEUER TRIPLE CALENDAR CHRONOGRAPH WRISTWATCH CIRCA 1950s, REF. 2923 D: Two-tone silver dial with applied luminous Arabic numerals, triple register recording hours, minutes & continuous seconds, inner day & month apertures, blue outer date calendar. M: 17 jewel manual wind movement signed Ed. Heuer & Co with Heuer emblem & numbered. C: Circular screw-back case, signed Ed. Heuer & Co with Heuer emblem & numbered, case diameter approx. 37mm. S: Black leather strap.