This is an old Seiko watch. It has a black metallic dial and an automatic winding function, with no manual winding function. It has a calendar display function. Pressing the recessed bezel at the 4 o'clock position in 0 steps advances the date. Pulling it out adjusts the time. There is no day quick-set function, and it changes when rotated for 24 hours. Waterproof performance is indicated (water proof), but details are unknown. It has 23 jewels. Model: 5126-7000 At the 6 o'clock position: JAPAN 5126 7000 AD (Water proof → Water Resistant was changed in the late 1970s, so it is believed to have been manufactured during the period from the 1960s when it was released until then) Other specifications: The appearance has a curved design. Case size (excluding the crown): Approximately 35mm Lug width: 18mm The SEIKO logo on the left side of the black dial is unusual. Wrist size: 18.5cm. It comes with a genuine leather band. It has little signs of use and is relatively clean. Fine adjustments are possible by moving the buckle to the hole. The exterior condition shows fine scratches on the stainless steel case and many fine scratches on the crystal. When worn, it has a refined and dignified appearance from a distance (see the photos at the end). It ran for a full 24 hours with an error of about 1-2 minutes. It is a fully functional watch that is not a problem for daily use. Please note that this is not an accurate measurement. Search keywords: Seiko SEIKO I am not familiar with watches, but I will answer any questions you may have as much as possible, so please comment beforehand. Thank you.