This Seiko Lord-Matic, Suwa division, is a self-winding 23 jewels 5601-9000 from September 1969. It has the King Seiko 56 base movement (a high end automatic that was thinner then all other auto’s of the time).
This Lord-Matic made by the Suwa division is large (35x42x10mm), it has a 21600 beat rate, offers time only, hand winding and the ability to precisely set the seconds though a hacking lever.
The 56 stream seems to have been developed between two other caliber streams, the 51 (starting in 1967), and the 52 (starting in 1970). When the 51 was developed, it had a thickness of 4.9mm. The 56 had a reduced thickness of 4.3mm, and the 52 further reduced the movements thickness to 3.9mm.
In this continuing effort to reduce the thickness of its mid to high grade movements, many novel design elements were incorporated into this 56LM.
At the beginning of their roughly ten year production run, during the late 1960's till 1970's, the Lordmatics were a one piece design (as this one is) in that you could only remove the movement from the front, thereby increasing the water-proofing. For maintenance of the watch, it is opened through and by removing the acrylic glass.
Although the 56 series was later upgraded and used in some chronometer grade King Seiko's, I find it sad that it was not chosen for the task when Seiko made the decision to resurrect the 52 series as the 4s15, with all of its siblings. I really think Seiko was approaching the epitome of automatic movement design in this caliber, and the 4s series is a compromise of some excellent ideas
This JDM edition then, English and Kanji (Japanese) day, is still moving flawlessly after a Seiko shake with a day difference within COSC. The wow factor is very much present with this one and the original stainless steel "beads of rice" band is a big factor in that. It is complete, and adjusts to roughly 17,5cm maximum. Spring loaded buckle extender is included of course so anyone can wear it now, not just the small tiny wristed Japanese of the late sixties.