The Osco 66D is a well equipped movement of german production: It contains a screw balance (or a golden toned ring balance in later issues), which is beared in a Trishock-like shock protection system, a direct driven center second indication and a date display by a date wheel. Only the rocking bar winding mechanism is a tribute to the economical fabrication of this movement.
This movement uses a number of cap jewels on the escapement and escapement wheel (on the dial side).
|Number of jewels:||17|
Glucydur screw balance|
Nickel anular balance
|Balance bearing / direction hairspring:||Counterclockwise|
|Adjust mechanism:||Hairspring key|
|Winding mechanism:||rocking bar winding system|
|Setting lever spring:||3 hole(s)|
Flume: 1957 36|