King Seiko 45-8010 Chronometer

HamDoctor

Thanks for the detailed breakdown! That was really amazing to watch, and I learned something new - didn't know that the serial number on the movement was associated with the Chronometer certification. I had been wondering why there were 4500 movements with and without serial numbers.

Just one very minor correction: these weren't COSC certified, as the COSC was not in existence then (it was founded in 1973). The King Seiko Ref. 45-8010 (along with it's "dated" sibling, the 4502-8000) was in fact the first chronometer that was officially certified in Japan by the the Japan Chronometer Inspection Institute (JCII, established December 1968). [Source: https://www.beyondthedial.com/post/king-seiko-collector-guide-part-2/ ]

Early examples like the one you showed had the inscription "Superior Chronometer Officially Certified", the later versions like mine from April 1970 "only" said "Chronometer Officially Certified".

I really love the design of the case! And a 36.000 bph manual wind movement certainly is a rarity. Here's a picture of mine:

HamDoctor

Thanks for the detailed breakdown! That was really amazing to watch, and I learned something new - didn't know that the serial number on the movement was associated with the Chronometer certification. I had been wondering why there were 4500 movements with and without serial numbers.

Just one very minor correction: these weren't COSC certified, as the COSC was not in existence then (it was founded in 1973). The King Seiko Ref. 45-8010 (along with it's "dated" sibling, the 4502-8000) was in fact the first chronometer that was officially certified in Japan by the the Japan Chronometer Inspection Institute (JCII, established December 1968). [Source: https://www.beyondthedial.com/post/king-seiko-collector-guide-part-2/ ]

Early examples like the one you showed had the inscription "Superior Chronometer Officially Certified", the later versions like mine from April 1970 "only" said "Chronometer Officially Certified".

I really love the design of the case! And a 36.000 bph manual wind movement certainly is a rarity. Here's a picture of mine: