Seiko 6139-7100 Helmet Case Chronograph

Seiko 6139-7100 Helmet Case Chronograph

Vintage Seikos are a terrific way to start any timepiece collection, and 6139 chronographs such as this one are about as unusual and cool a timepiece design as you can get. Don't be fooled into thinking that these are run-of-the-mill.  These timepieces house Japan's first automatic chronograph unit, which came out concurrently with those from Zenith and Heuer around 1969 and is considered one of the world's most important movements.

Although Seiko produced these on a scale unmatched by their Swiss counterparts, finding original examples in excellent condition is tough, and a quick scan through the pages of eBay will show you just how many watches have been modified with mediocre aftermarket parts. Maintaining and ensuring originality is of course a challenge with any vintage watch, but it may be the hardest with Seikos and Citizens due to the tremendous number of "frankensteined" watches on the market.

This particular chronograph is a reference 6139-7100 dating from approximately 1977, and has what is affectionately known as a "Helmet" or "Darth Vader" case, due to its massive size and steeply angled lugs. It is in entirely original condition, save for a genuine replacement bracelet from a later model, and is a stunning example with its dark dial and bright yellow hands. Its size makes it eminently wearable by modern standards, and the quickset day/date functionality makes it a pleasure to use daily.

While you could find a less expensive example, you won't find another that is guaranteed to be 100% original and looks this damn good. If you're kicking off a watch collection, or visiting a new segment of the vintage market, this is quite simply a great catch.


Stainless Steel compressor case is approximately 41mm (excluding crown). Seiko reference 6139-7100. Circa 1977.

Overall condition: Case is in very good condition over all with only light wear consistent with age. Original dial is in very good condition with no noticeable depreciation and a pleasant light patina. Original hands are in excellent condition.

Includes stainless steel bracelet with Seiko signed clasp. Also includes two 20mm Nylon Straps by Crown & Buckle.

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