OMEGA TRIPLE CALENDAR AND MOON PHASES Omega, Triple Calendar and Moon Phases, Ref. 156.003, movement no. 37036651, circa 1983 A fine and unusual, automatic, tonneau-shaped, 18K yellow gold, triple calendar wristwatch with off-white dial, gold leaf hands, applied radial gold Roman numerals, apertures for the day and month, moon phases indications, outer minute division with 5-minute radial Arabic numerals, leather strap and gilt Omega buckle. Fitted with a Cal. 715, mechanical, gilt finish. 24 jewels, self-winding, straight line lever escapement, four-arm monometallic balance, flat balance spring, shock-absorbers, sapphire-set snap on caseback, sapphire crystal, correctors in the lugs, gold Omega crown, stepped and rounded gold bezel, steeped lugs. Dial, case and movement signed. Diam. 34.80 mm. Thickness 8.60 mm. Omega Ref. BA 156.003 was introduced in 1983, featuring an 18K gold case, caliber 715 self-winding, a sapphire-set case back and water resistance to 30 meters.