This watch is a little substandard as far as condition goes but it’s the only Seiko three register chronograph that I have so here it is. (Not any more! I now have another, that has been posted)
The Seiko 6138 competes squarely with the more sophisticated Swiss Chronographs that were on the market at the time. Unlike the 6139 which was aimed, by price, purely at the mass market, this has two sub dials making it a 3 register, rather than the 6139’s 2 register and has auxiliary manual wind. These extra features make the movement quite bulky, 8mm thick compared to 6.9mm for the 6139A. But bulk in the 70s was good. In fact this watch has a ridiculously thick glass to match it’s thick case making it a hulk of a watch. This movement was made from 1970 to 1977 and this watch is 1977 so it was amongst the last of the Seiko mechanical chronos.
The glass has been replaced and is pristine but the dial is poor, faded with the chapter ring and tachymeter ring faded and possibly affected by moisture damage. It is signed 4 times and would have been a head turner in its day….but not any more.