The last model Contax cameras had gold serial numbers on the flash shoe. They also had spring clips for the take-up spool so it would not fall out. The meter rode on ball bearing and was very accurate. (list price for the IIIa (with 50mm f1.5 Sonnar) in 1960, $288) catalog number 10.1813
Before WWII plants in Dresden, Jena, and Stuttgart had several thousand workers. During the war the city of Dresden was mostly destroyed by bombing. Once the war ended the remains of the plants under Russian control were reassembled. Many of the engineers and camera assembly people escaped to Stuttgart. A new Zeiss Ikon factory was set up in Stuttgart. Introduced around March 1950 in this country the Contax IIa and IIIa were beautifully made machines. The post-war cameras were more refined, better machined, and smaller than the pre-war Contax cameras. There were two versions of the IIa and IIIa Contax cameras. The black dial camera (the speed dial is all lettered in black) needed a special sync cord for the flash (1361 bulbs, 1366 electronic flash). The red dial camera (the later camera) had a modern day PC fitting for electronic flash.