Model: Carrera DatoReference: 2547SDate: Circa 1972Movement: 17-jewel Valjoux Cal.723 manual wind, signed Heuer Leonidas on the bridge Dial: Silvered, applied polished baton hour markers, black outer 1/5th second divisions with Arabic five second markers, outer blue calendar indications, engine turned subsidiary dials at 3, 6 and 9 for constant seconds, 30 minute and 12 hour recording, day and month apertures at 12, polished pointed baton hands with luminous inserts, centre chronograph hand, red crescent tipped calendar handCase: Brushed and polished round, snap on back, crown flanked by twin pushers, quick set buttons set in band at 9 and 10, No.177595Strap/Bracelet: Black calf skinBuckle/Clasp: Signed stainless steel buckleSigned: Case, dial & movementSize: 36mm