About the 6138-3009

The Seiko 6138-3009, often nicknamed the “Jumbo”, is one of the standout models from Seiko’s legendary 6138 chronograph line, produced in the mid-1970s. The 6138 series was a major step forward for Seiko—it featured fully integrated automatic chronograph movements with a column wheel and vertical clutch, rivaling and often exceeding the complexity of Swiss counterparts of the era. The 3009 was a North American export version of the 6138-300X family, known for its imposing case size, excellent legibility, and robust construction, earning it the “Jumbo” moniker among enthusiasts.

What makes the 6138-3009 particularly notable is its clean, symmetrical dial layout, durable movement, and distinctive 1970s case design. Unlike some of its more flamboyant siblings (like the UFO or Bullhead), the Jumbo is all about functional elegance. It features dual subdials, a 12-hour totalizer at the top and a 30-minute counter at the bottom and a day-date complication at 3 o’clock, all while maintaining excellent dial balance. The 6138 movement also allows for both automatic and manual winding, which was a unique for Seikos of the era.

About this example

This6138-3009 shown here has a matte black dial with recessed subdials and bold white markings, offering superb legibility. The yellow chronograph seconds hand adds a punch of color, while the hands and indices catch the light for easy reading. The case, a large (for its time) 42mm stainless steel cushion shape, has a utilitarian brushed finish with pump pushers flanking the crown. It’s presented on a black NATO strap, complementing the watch’s rugged tool-watch aesthetic. This example comes to you freshly serviced by us with a new crystal and keeping excellent time. The hour and minute hands appear to be high quality aftermarket.