Breadcrumb
Date
The day of the month, displayed in a window on a watch dial at the 3 or 6 o’clock position, or within a subdial at 9 o'clock.
Helium escape valve
Decompression system which allows helium to escape from inside the watch when the watch is worn for professional use in pressure chambers. (Long-term underwater work, crude oil exploration, etc.)
Screw-in crown
Self-locking crown, screwed into the tube of the case, used for highly water resistant divers' watches.
Unidirectional rotating bezel
A bezel which turns in only one direction. Particularly useful for divers who cannot accidentally rotate it in the wrong direction, which could cause them to miscalculate their dive times. A rotating bezel makes it easy to measure elapsed time.
Get the latest edition of our official Omega catalogue "The Collection".