Hi all, I have four, 24 tooth, flat foot crowns which all measure 6.72mm. Three of the crowns have a height of 3.83mm which I believe to be correct for cal. 321 Speedmasters, but one measured at 3.34mm in height, so I’m not sure about the shorter one. If anyone could help I’d appreciate it.
Can you measure the thread size of the stem ? That will differentiate immediately between Speedmaster, Seamaster, and Railmaster.
That’s a great piece of information. Unfortunately it doesn’t have a stem, but could you please tell me which watches correspond to which thread sizes of stems?