: Mark that is misleading because all the watches have little
: Ts hence watches shown would be before 1969 !!

I want to follow up on the tritium story a little more at some point. I have found that the use of tritium in watches is governed by ISO 3157, originally from 1975 and updated in 1991. I'm a little loath to shell out for the 1991 standards document as it may not have the references to prior legislation that the original, now deprecated standard probably had. I'm not much interested in how tritium is permitted for use now, so much as the regulations that began to be introduced around it in the 60s. Heuer had clearly stopped using it in civilian applications long before that first ISO standard appeared in '75. I'd guess that one of the major export markets tightened its controls on tritium import fairly early on, and I'd also guess that that market was the US but it really needs some more digging around.

Any Bundeswehr experts know offhand whether all the watches were marked with either T or 3H, or if any didn't use tritium? Even the chronomatic prototypes were marked 3H as I recall...