This Seiko Bell-Matic 4006-7010 from January 1968 is a special one:
It is the first and only 7-digits-serial number I ever seen on a Seiko from 1968.
Until some weeks ago I thought, that Seiko has used the 7-digits-serial numbers from 1961 until the end of 1967. But this 7-digits Bell-matic is from January 1968.
Here are some pics:
VintageKing (announced by TheNeilo)
Maestro of WISdom (announced by Poseidon-Jim)
"Man invented time, Seiko perfected it."