The Eterna 403 watch movement, introduced in 1947 and renamed from Omega 27DL PC AM in 1948, is a manual wind movement with a sub-second function. It features additional functions such as day and date display, which can be set using pushers at 4h and 2h respectively. The moon phase display, exclusively set by the pusher at 8h, adds to the movement's calendar features. Notably, the Eterna 403 movement was utilized during the period of 1947-1948.