Original von Idle Swede
My favorite movement is the 650.
Wow, a very sophisticated caliber with a height of only 1.8 mm (!). The 650 was introduced in 1958 and was used (amon others) in the King Midas. I assume your lovely Midas is the reason for the unusual choice of your favorite caliber.

For those who don´t know the 650, please find following a scan from an old spare parts catalog (R4):



In 1978 the improved caliber 651 with 18 jewels (650: 17) and 21,600 A/h (650: 18,000) was introduced.

Regards
Matthias