Seiko's 6138 is the sophomore release to the 6139 and adds a few features lacking on the former. In addition to the rolling 12 hour register, it could also be manually wound at the crown, and the day and date could be quick set independently. The "bullhead" earned it's nickname when Seiko decided to rotate the movement 90 degrees within the case, and position the crown and chronograph pushers at the top of the case creating its resemblance to a bull's horns. At nearly 44mm, it is truly a beast, and the gradient brown dial, gold sub registers and "root beer" bezel offer an excess of 1970's appeal. Introduced in 1974, this 5 Sports Speed Timer variant from September of that year was created for, and sold only to the Japanese domestic market. Setting it apart from its export counterpart, it bears the “5 Sports” and “Speed Timer” badging on the dial just beneath the Seiko logo, and the hands and hour markers are painted a stark flat white throughout, rather than given a luminous finish. Instead of yellow, the chronograph sweep hand is a deep fiery orange, and the day can be toggled between Japanese (Kanji) and English. It’s unpolished and completely original aside from a replacement crystal, and post service the 6138B is keeping near perfect time. The chronograph functions are smooth and responsive, and we’ve paired it with a steel gray “Tropic” that partners beautifully, and provides and comfortable fit and finish. If a robust, and burly vintage racing chronograph with JDM credentials is on your list, this one will be hard to beat.

CNS “Tropic” Style Gray Silicone Rubber Strap

Serviced 8/1/21

Diameter- 44mm

Lugs- 20mm