Да, чуть не забыл - COSC существует с 1973 года (это к надписи на цифере, кроме моих предыдущих замечаний...)
До того (до 1973) подобие сертификации проодилось исключительно в Свиссии:
While competitive chronometer testing took place at the observatories in Neuchâtel (1866–1975) and Geneva (1873–1967), testing of large numbers of watches intended for public sale was conducted by the independent Bureaux officiels de contrôle de la marche des montres (B.O.s) established between 1877 and 1956. Between 1961 and 1973, “a chronometer [was] a precision watch, which [was] regulated in several positions and at different temperatures and which had received a certificate [from the (“B.O.)]." Collective certificates, rather than individual certificates, were usually issued. The 1961-73 standard required a mean daily rate in five positions of -1/+10. In 1973, the B.O.’s came under the C.O.S.C. which specified a daily rate of -4/+6 sec.
Представить себе маркировку хронографа на цифере в штатниковских часах с омеговским калибром возможным не представляю ;0)
Вывод - либо разводят нас, либо ТС