Where does this case part go?

[Charette]

Hi all - silly question maybe - I have the below watch case and in addition to the movement ring, it has a large flat ring. Does this go behind the dial, or in front of the dial?

Big silver ring in the photo. It is flat. Cannot see this in other build your own watch videos online. 

Thank you

[HectorLooi]

Where did this case come from? What movement are you using?

[Kalanag]

If it is needed to align the movement with the crown tube it should be placed in front of the dial. If not it goes into the case back.

[HectorLooi]

Haha. I just realized what you are referring to. That is the exhibition caseback with the glass porthole.

[Charette]

Hi all, thanks for the replies. 
I am referring to the ring in top left of the photo. It is a simple flat ring - tried to take a better photo of my own. 
I finished assembling the watch tonight and I had it in front of the dial - was too tight to squeeze over the movement - but it was peeking out slightly when viewing the dial so I’ve just taken it out and not used it. With the movement ring everything still does up tight with no shakes so I am thinking I am just going to leave it out.

The case is from AliExpress, movement is seagull st3621, tried out one of the ‘make it yourself from internet parts watches’. No description of the extra ring in the ad.

Here is the ad - based on the parts described, I don’t think that silver ring is mentioned. 
I took the ‘movement cushion mount’ to mean the movement ring.

Edited September 28, 2022 by Charette
Typo

[HectorLooi]

Some of these are dial spacer rings. They go under the dial to ensure that there is space for the motion works.

Other times, the case might have been designed for more than one movement and this ring is meant for that.

[Charette]

1 minute ago, HectorLooi said:

Some of these are dial spacer rings. They go under the dial to ensure that there is space for the motion works.

Other times, the case might have been designed for more than one movement and this ring is meant for that.

Interesting, thank you. I just finished up so will have to see how it keeps time. Hopefully all is ok - the dial I purchased, supposedly for ST36* movements, had feet barely long enough to fasten (that is another story on its own) so I would be out of luck if I had to add the ring behind the dial. 

[HectorLooi]

8 minutes ago, Charette said:

Interesting, thank you. I just finished up so will have to see how it keeps time. Hopefully all is ok - the dial I purchased, supposedly for ST36* movements, had feet barely long enough to fasten (that is another story on its own) so I would be out of luck if I had to add the ring behind the dial. 

I just checked Aliexpress, the case is also meant for ETA 6497 and ETA 6498. So hopefully the ring is not intended for an ST3600.