The first image is a reference. Circa 1974, Cal. 6810, Hand-wound, Made by Daini Seikosha This is a SEIKO "6810," an ultra-thin, high-end dress watch. The case and buckle are made of 18KWG (18K white gold), giving the watch a very luxurious feel. It was manufactured in 1974 by Daini Seikosha. The book published by Tonbo Publishing details the "68 series movement." In its initial design phase, it was even featured in "International Watch Communication," the world's most reliable watch magazine, where its accuracy and reliability were highly praised. While AP, Jaeger-LeCoultre, and Piaget are famous for their thin movements, the "68 series movement" continues to be produced today as a thin, high-precision caliber. The number of watches produced was extremely limited, making this a very rare timepiece that fully embodies the true excellence of the Daini Seikosha-made "68 series caliber." The 68 series is still used in Credor watches and other "high-end thin watches." The movement is only 1.98mm thick, and the entire case is about 6mm, making it a top-of-the-line hand-wound watch designed with thinness in mind. The dial and hands are in very good condition considering the manufacturing year. The case and back cover show some scratches and hairline marks from use, but there are no noticeable dents. The buckle is the original 18KYG (18K yellow gold) one. The crystal has minor scratches. A spare strap and buckle are included.