Seiko 5 Sports introduces a limited-edition collaboration model with HUF. Based on an archival Seiko model from the 1970s, affectionately known as the “Time Sonar,” this special timepiece has been reimagined with HUF’s unique style and finished with exclusive design elements. The first ever Seiko 5 watch, Seiko Sportmatic 5, was born in 1963. It was Seiko's and Japan's first ever automatic day-date watch. ''5'' represented the promise that every Seiko 5 watch would have five key attributes.Taken together and in combination with the then new mainspring and shock resistance system, these features gave Seiko 5 its distinctive appearance and its strength.Five key attributes automatic movement day-date display at the three o'clock position water resistance recessed crown at the four o'clock position case and bracelet built for durability Seiko 5 Sports Orange Dial Features: calibre 4R36 with manual winding capacity 41 hour power reserve: (approx.) 24 jewel stop seconds hand function stainless steel case Hardlex crystal screw case back see-through case back Lumibrite on hands and index markers stainless steel bracelet with three fold clasp water resistant to 100 metres LIMITED EDITION on the case back Serial number engraved on the case back case thickness: 11.6mm case diameter: 39.4mm lug width: 20mm