I recently acquired a ‘Pre Must’ Cartier Tank Louis with reference no. 15705 that I believe dates back to the early 1970s. It was made during the time when the Cartier boutiques were operated separately in New York, Paris and London.

I would love to know more about this watch so if there are others out there who own this piece, please share some photos and information on when and where it was purchased! I am no expert so all the information that is written in this post have been compiled after hours of research.

This Pre Must Tank has a manual wind Cartier 78X movement (ETA 2512 base). Later manual wind Must models from the late 1970s use the Cartier 78-1 movement (ETA 2512-1 base) instead.

Its size is approximately 30mm height by 23mm width excluding the crown, making it the model for men at that time.

This post only includes pictures of pieces with screw on case backs and punched logo, which is said to be from the New York boutique. Pieces with snap-on case backs have been excluded as they seem to be far more common.

After hours of scouring the internet, these are the information I could find.

From the internet:
- Ref. 15705 Tank Louis is from the New York boutique
- Due to the use of a patented screw-on case back, back then in the early 1970s, this particular reference could not be faked.
- Gold plated over base metal (likely brass)

From observation:
- White dial with SWISS under VI
- Elongated blue carbochon crown
- Earlier serial numbers seem to have a thicker crown
- Unlike the Must series, there is no hidden Cartier mark on VII, or on X like other modern pieces
- The first number 4 on the case back seem to indicate that this is for men. The smaller sized pieces with the same case back markings start with a 1
- The original buckle for the strap has a double C logo that looks very similar to Chanel

Pictures of this ref. 15705 with smaller serial numbers seem to also have a long 10 digit reference number of some sort engraved on the inner side of the case.

I only own 1 of the watches below. The other pictures were taken off of the internet.

1. This is the copy I own
Serial number on case back: 4 00014
Innerside of case back: 15705 7808600867






2. Not mine
Serial number on case back: 4 01005
Innerside of case back: 15705 7808600699




3. Not mine
Serial number on case back: 4 02210
Innerside of case back: ?????



4. Not mine
Serial number on case back: 4 03748
Innerside of case back: 15705





5. Not mine
Serial number on case back: 4 04???
Innerside of case back: 15705




6. Not mine
Serial number on case back: 4 05101
Innerside of case back: ?????



7. Not mine
Serial number on case back: 4 05217
Innerside of case back: ?????



8. Not mine
Serial number on case back: 4 05945
Innerside of case back: ?????



9. Not mine
Serial number on case back: 4 09730
Innerside of case back: 15705




10. Not mine
Serial number on case back: 4 0????
Innerside of case back: ?????



These are all the pictures I could find on the internet. It seems quite elusive but I may be wrong. Please let me know!

This is the strap buckle for this model. It was more square and had interlocking Cs.




Once again, I am no expert and the information written in this post stands to be corrected!

Regards,
Hensley

 

Heyoo,

I know this was a couple months ago, but every once in a while I Google the 15705 because I have one and want to see what's going on in the market, etc.. I stumbled upon this post and just wanted to reply to let you know I have the same one as you. You seem to have an earlier Serial, as mine starts in 4_08. Not much information, as you already touched upon everything you've found. I bought mine at an auction (along with one that ended up being a fake), but same movement as yours with the 78X. My strap seems to have been replaced at some point, as I do not have the Cartier one, nor buckle on it.

Does yours have the blue hands, or is that the picture making them look black? Mine hits all of the same marks as yours. My crystal is a little beat, and I wonder if it's even possible to replace. Seems to run fine, I haven't done a test or had it serviced to see the condition of the movement. And I believe you are right about the Brass as the base of the metal.

I noticed you also found that Youtube Video of Wristwatch Revival that did an in-depth. Pretty cool watch, are you wearing it or just holding on to it? I want to find the right strap -- Green, Blue, or Grey Suede and make it pop. I originally thought I would just flip it but I dig it and it's a classic.

 

Thanks for compiling all this info! Very helpful and well presented
I like the elongated cabochon quite a bit, though always found the buckle peculiar. The design seems at odds with the general aesthetics of the Tank's case.

 

Dear Hensley,

Thank you for the amazing work! Very interesting research!

I just bought one quite similar one but i am not sure it is authentic...Nothing on the back case. What are the thought of the community? Thank you!

 

Hi there! The hands on my watch are blue, but the pictures make them look black.



I wear mine almost everyday. I managed to find an aftermarket crystal on Aliexpress for less than 20usd and did the replacement myself. I can share the link if you’d like so please drop me a pm. I also found 2 period-correct replacement cabochon crowns on *bay and used 1 to repair the piece I have. The crown in the picture is the one I replaced. I am keeping 1 as spare since they are hard to come by!

Regards,
Hensley

 

You’re welcome! I also find the elogated carbochon crown very appealing. The buckle, not as much. I still use the original buckle though, for that “complete” look.

 

Hi! I think this might be a redialed Catena watch. The Catena logo is on the case back.

Regards,
Hensley