What is the metal disk glued to the cover of a digital watch?

[38034580]

When taking apart a digital watch, I see a golden disk glued to the back cover. What is it? What is it used for?

[CommanderAlex]

Can't tell due to the horrible picture quality. 

[si1enze]

What watch make and model, and yeah the picture is pretty bad.

[GuiltySpark_]

That picture is not telling me anything. No idea what i'm looking at.

[The_russian]

 

@CommanderAlex @si1enze @rickeo 

Found a watch that has something similar, not sure if OP is asking about the gold-ish disk or the inner disk. Gold-ish one is metallic, inner one feels like paper or fabric. Totally a guess, but maybe to absorb moisture/humidity?

 

Edit: This is on the backside of the battery/back cover.

 

Edited September 25, 2021 by The_russian

[CommanderAlex]

1 minute ago, The_russian said:

 

@CommanderAlex @si1enze @rickeo 

Found a watch that has something similar, not sure if OP is asking about the gold-ish disk or the inner disk. Gold-ish one is metallic, inner one feels like paper or fabric. Totally a guess, but maybe to absorb moisture/humidity?

 

~Sniped Photo~

Hmm, perhaps like a desiccant? 

[si1enze]

Is that in the same place where the battery resides?

[The_russian]

5 minutes ago, CommanderAlex said:

Hmm, perhaps like a desiccant? 

That’s my guess, but if not I’m curious what it is. 

[The_russian]

1 minute ago, si1enze said:

Is that in the same place where the battery resides?

I edited my post to add the info, but yes it is on the backside of the battery cover.

[GuiltySpark_]

7 minutes ago, CommanderAlex said:

Hmm, perhaps like a desiccant? 

Probably exactly that. Some kind of humidity monitoring tag. Like this maybe? 

 

https://www.aliexpress.com/item/32408500278.html

[si1enze]

Just now, The_russian said:

I edited my post to add the info, but yes it is on the backside of the battery cover.

Brass is more corrosion resistant than steel or even stainless steel.  That's is probably why, in case of battery leakage..

[mariushm]

It's a f...ing piezo speaker ... it beeps.

 

 

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