This is a reproduction Base 1000 "Dot Over Ninety" Bezel for the Omega Speedmaster, Professional and Straight-lug variants.
If you are unsure whether this bezel will fit your Speedmaster, please contact me. It is also available at a discount on the Spiralwinder Watch Parts website. 

this bezel can be mounted to the straight-lug and professional Speedmaster cases without issue. Since all pre-3861 Speedmaster bezels are interchangeable, this will be able to press on to the cases of all the manual wind 321 to 1861 Speedies. 

It has the same semi-gloss, anodized finish that a bezel from the 60s would exhibit if new. It also has the same serifs and font as an original bezel. The steel ring is made from 316L stainless steel, and the insert is anodized aluminum — identical to the originals in composition.

To reiterate, this is not a vintage bezel — it is a modern replacement

These bezels have become exceptionally rare, and I have personally known some who have lost or severely damaged theirs upon accidentally knocking their watch against something. This reproduction is meant to be a solution for those who would not like to risk the damage or loss of their valuable vintage bezels.

This has all the correct dimensions, measurements, and serifs of a vintage bezel except for some very slight alterations which have been made to ensure that this cannot be passed off as a vintage piece. 

If you have any questions, please feel free to send me a message.