Seiko Bullshead 6138-0040
The Seiko Bullhead 6138-0040 was introduced in 1969 as part of the “Seiko 5” family according to the Seiko website.
The Bullhead was primarily marketed as a driver’s watch as the orientation of the case has a slight tilt at the 12 o’clock position to give it functionality when used in a motorsport setting.
The outer bezel of the Seiko 6138-0040 is non-rotating. it is inscribed with a tachymeter, a scale which drivers use to measure speed over a given distance.
The 6138 movement was developed by Suwa Seikosha. The world’s first automatic chronograph movement that features a column wheel and a vertical coupling mechanism.
The 2 sub dials for the Seiko Bullhead feature a 30-minute and 12-hour register and a 60 second sweep. The numbering of the Seiko 6138-0040 came in Arabic numerals. The Bullhead watch hands come in the pencil-style and are white. The Chronograph come in black and the sweep second hands are yellow on the Chronometer. The day wheel of Seiko Chronograph model is written in either English or Spanish.
The Bullhead is one of the biggest and bulkiest watches ever produced by Seiko. It measures 44mm in diameter (with a length of 45mm from lug to lug) and a height of 16mm. It is also one of the thickest Seiko watches available. The relatively large size of the Seiko Bullhead contributes to its appeal and desirability; yet, this very trait makes it vulnerable to the everyday wear and tear, and few models have survived without nicks and scratches.
This Seiko 6138-0040 Bullshead has 21 J and dates back to April 1977