Seiko produced Stellaris for Sears, Roebuck, and Company as the in-house brand for Sears – and this crisp deep blue 1970s Stellaris "Electronic" transistorized rally diver is no different. 
 
Seiko and Stellaris did their homework when they designed these deep blue dials, and pictures do not do these justice - these dials are amazing to behold in person, and this dial here is no different.
 
Stellaris Electronic Transistorized watches are vintage transitional timepieces - bridging the gap between mechanical and quartz - from the mid-1970s that use a battery-powered balance wheel movement regulated by electronic components instead of a traditional mainspring.  
 
The movements in these Stellaris watches are all Seiko 3302A although you’ll be hard pressed to see any identifying markings other than those of the retailer - nevertheless, the movement carry's a rather noticeable "Made in Japan" on it.   The 3302A runs at 21,600 BPH and is similar to the later Seiko EL-370.  
 
At its 1886 inception, American company Sears (run by former railroad agent Richard W. Sears) sold watches by mail order catalog; much akin to Amazon selling books at its founding, pocket watches were Sears' first commodity, and Sears would gradually add substantially to its catalog offerings, much like Amazon online.
 
Japanese watch company Hamazawa Ltd – founded in 1954 – had an unofficial relationship with Seiko.  In the 1970s, Hamazawa took out several joint patents with Epson (one of the three core companies of Seiko Group in contemporary times) on non-watch related items.  
 
Hamazawa appeared to have sold a lot of movements to various Japanese and foreign watch companies, and in 1983, it merged with two other companies one of which was a major watch case supplier for Seiko-Epson.  Subsequently, in 1986, this company was taken over by Seiko.

That said, we are getting ahead of ourselves – back in the 1970's, when this watch was made, Hamazawa was most likely somewhat independent; however, the mechanism on some of its mechanical movements required a license agreement with Seiko who held the patents at that time.  The Hamazawa/Seiko movements were sold widely overseas and may be found in U.S. brands including Sears, Benrus, and the British brand Astral.
 
Although Seiko produced Stellaris for Sears, preceding this, Stellaris was a brand name registered in 1963 by Mondia;  while not a well-known brand, it produced some intriguing watches, such as the Mondia “Big Eye” chronograph and the Top Second.  It also put out a watch model called Stellaris with an unusual fluid case.  
 
How did Mondia and Stellaris evolve to be separate watch brands?  No idea – another mystery lost to the ages, akin to how both brands would become victims of the Seiko-initiated Quartz Crisis.  Watch periodical Fratello speculated, “Mondia was used as support to make Stellaris trustworthy." 
 
"Or, I suppose another possible scenario is that the Mondia Stellaris became so popular that Mondia decided to make it a separate brand featuring its own range of watches.  And there were quite a few of them, mostly later Stellaris electronic models.”  Regardless, the Stellaris font and symbol didn’t change after it was established as a stand-alone brand, the clearest evidence of the relationship between the two.
 
This Stellaris Electronic diver comes on a leather strap, and with nylon strap, rugged travel case, and springbar tool.