The Ref. 5512 from 1959 has almost all the things we would search for on the current Submariner. Its situation experienced developed to 40mm, up from your 37mm to 38mm of previously pieces. Crown-guards were being included, and also the bezel now a bit overhung the facet of the situation https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/