Tissot 15TL chronographes with unsigned case backs

gotthevintageflu · Sep 23, 2026

Hi,

I stumbled on a number of Tissot 15TL monopusher, apparently from the 30s, all sharing the same dial but also a case back with a 5 digits serial number only (for this period, should be 6 digits at least) and no Tissot marking on the case back.

Everything else seems legit, but I don't know about the case back and why they would have been replaced. There must be a story behind this.

I found 5 like these.

What do you think? Legit case back or later replacement?

Thanks.

Redondo444 · Sep 23, 2026

I think it's legit.

Here is a 6th one:

This ad was posted here I guess by @Vitezi:

Could be a Lemania internal number.

Maybe an extract of Tissot archives will help?

gotthevintageflu · Sep 23, 2026

Redondo444
I think it's legit.

Here is a 6th one:

This ad was posted here I guess by @Vitezi:

Could be a Lemania internal number.

Maybe an extract of Tissot archives will help?

Interesting. Thanks for the feedback!

I don't think the numbers are Lemania serials. From what I could see, in the 30-40, Lemania serials were close to the 12xxx range.

However, using your hint, I searched for Lemania 14TL chronographes of this period, and they seem to have similar case backs, unsigned and serials in the 4xxxx and 5xxxx.

Maybe Lemania produced the early 15TL watches for Tissot and didn't sign the case backs in the begining?

Vitezi · Sep 23, 2026

gotthevintageflu
What do you think? Legit case back or later replacement?

Indeed, the early Tissot chronographs with either 15''' or 15CHT movements can have five-digit unsigned casebacks in the 30000 range. A batch of later 15TL movements were also shipped with five-digit casebacks. Lemania did produce all of these chronographs for Tissot and Omega. Knowing which caseback is correct for which movement and dial helps the astute collector sniff out frankens.

gotthevintageflu · Sep 24, 2026

Vitezi
Indeed, the early Tissot chronographs with either 15''' or 15CHT movements can have five-digit unsigned casebacks in the 30000 range. A batch of later 15TL movements were also shipped with five-digit casebacks. Lemania did produce all of these chronographs for Tissot and Omega. Knowing which caseback is correct for which movement and dial helps the astute collector sniff out frankens.

Thanks. This is a very useful information.

Now that you mentioned 15'' and 15CHT, I just noticed that I've been using 15TL for all of them (as most listing do BTW). And the one I am after has a 3xxxx serial and based on the chrono bridge, it is a 15'' (or LWC 15 from the cliniquehorlogere.ch). So that seems to match the pattern you mentioned.

Vitezi · Sep 24, 2026

gotthevintageflu
Now that you mentioned 15'' and 15CHT, I just noticed that I've been using 15TL for all of them

I use this designation :

gotthevintageflu · Sep 24, 2026

Vitezi
I use this designation :

Thanks. Looks like cliniquehorlogere.ch mixed between 15''' and 15CHT.

For which book or source is this?

Tissot 15TL chronographes with unsigned case backs

gotthevintageflu

Redondo444

gotthevintageflu

Vitezi

gotthevintageflu

Vitezi

gotthevintageflu

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