The Seiko 6138 "Yachtman" automatic chronograph, aka the “UFO” - like this all original example here - has a well-known cult status, hence the nickname “UFO” (although advertised by Seiko as the “Yachtman Chronograph”) due to its flying saucer-esque case design.
The UFO features innovative and simple construction, such as a unique lug-less case, very indicative of the 1970s in which it was made, its pushers ( held in place by the movement’s space ring) and crown are well proportioned for the case size.
The oddly numbered 6138 was the successor to the 6139 - the world’s first automatic chronograph - after its introduction in 1969, and the 6138 followed closely behind and was likewise produced by Seiko until 1979. The main differences between the 6138 and 6139 is the 6138 offers hand-winding and featured two chronograph registers versus the sole one on the 6139.
Further, the Seiko 6138 contains subdial registers measuring minutes and hours, whereas the 6139 only measured minutes. Inside, the UFO features a column wheel and vertical coupling – all hallmarks of a serious chronograph movement.
The UFO’s black dial is nicely contrasted with silver subdials and orange/red highlights on the central chronometer hand, dial and the external tachymeter bezel, and its fully integrated chronograph render it truly a landmark design, easily pitting it against the Zenith El Primero.
This Seiko UFO comes with an original bracelet, nylon NATO strap, spring bar tool, and Pelican travel case.
1970 Seiko 6138-0019 Yachtman "UFO" Automatic Chronograph
DIAL: Original "water-resist" and Seiko-signed black dial - orange on dial remains vibrant with zero fade, unlike on most UFO examples. Day/date - with English/Spanish day variants - at 3 o’clock position works nicely. Original hands are in good condition, and retain a nice uniform lume.
CASE: Original 44mm (w/o crown, 46mm with) x 47mm stainless steel case; matching original caseback. No evidence of machine polish, bezel has several small scratches, with largest at 3 o'clock position. Bezel insert is excellent, with limited to no fade, but with some limited damage betweem 2 and 3 o'clock position.
CRYSTAL: Correct hardlex crystal, no scratches or blemishes.
BAND: This UFO comes with an original Seiko-signed stainless-steel Steluxbracelet, with the original owner's initials inscribed on the buckle, and will fit up to an 8 inch wrist; it also comes with a dark blue and red nylon NATO strap.
MOVEMENT: Original 21-jewel Seiko 6138 automatic movement, manufactured in June 1970.
CROWN: Original unsigned stainless steel crown.
CHRONOGRAPH PUSHERS: Chronograph pushers depress with satisfying click, no stick. All chronograph hands reset to 0 as designed.