This is the Omega Seamaster Automatic Dual Calendar watch. It houses the iconic Cal. 1022 automatic movement, a hallmark of Omega's golden age, renowned for its precise timekeeping and date display. The case is plated with a 20-micron-thick gold plating process. This advanced plating technique is thicker and more scratch-resistant than ordinary plating, maintaining its dazzling golden luster to this day. Paired with a gold sunburst dial, the watch appears as good as new, making it a truly rare and exquisite piece. 【Brand Series】Omega/Seamaster Series 【Official Model Number】166.0210 【Year of Production】Approximately 1978 (Movement Serial Number 4124xxxx) 【Core Movement】Original Cal.1022 automatic movement (17 jewels/with stop-seconds function and automatic/manual winding) 【External Materials】High-grade 20-micron gold-plated case (PLAQUE OR G 20 MICRONS), original Ω-marked crown 【Dial Size】Original gold-plated sunburst dial | Case diameter 35.5 mm (excluding crown), original Ω-marked crystal 【Strap】Non-original brand new gold-plated stainless steel bracelet, robust construction, can be worn up to 21 inches wide 【Product Condition】Inspected, the rose gold plating of the movement is extremely clean, with no obvious wear; timekeeping and quick-set functions are normal. 【Functions】This watch supports both manual and automatic winding. Adjusting the Date: Pull the crown out to the first position and rotate it up or down to quickly change the date. Adjusting the Day of the Week: Pull the crown out to the second position and rotate the hour hand counter-clockwise until midnight to change the day of the week. It also features a stop-seconds function. (Old-fashioned mechanical watches are precise; please do not forcefully adjust the date between 9 PM and 3 AM to avoid damaging the gears.) Shipping: Delivery Method: Postal delivery, EMS. Estimated arrival time: 5-20 days after shipment. Arrival time may be delayed due to postal service or customs procedures. A tracking number will be provided. Customs and Taxes: Additional customs duties or taxes may apply depending on the import regulations of your country. These costs are borne by the buyer. It is recommended to check local customs policies before purchasing. After-Sales Support: We are a second-hand watch and antique dealer from Taiwan with over 20 years of experience. We aim to provide you with unique vintage watches. Upon receiving the watch, please carefully inspect it to ensure everything is working properly. If you encounter any problems, please feel free to contact our after-sales support team. We are committed to resolving issues quickly and professionally. ~~Please don't forget to leave positive feedback to express your satisfaction~~