This movement was the latest one of the original “Duromat” Series, which were produced for about ten years, starting in 1952 with Caliber 552. The base movements and selfwinding mechanism were improved several times.
The caliber 590⁄1 does no longer use a screw balance, but a simple nickel balance without regulating hand. The selfwindig mechanism was fully equipped with jewels, which lead to the impressing number of 30 functional jewels. It also uses a large date indication ring.
|Number of jewels:||30|
Nickel anular balance|
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Hairspring key|
|Functions:||hour, minute, second, day, selfwinding|
Flume: 1962 74|