Bezel Inserts for the GMT - Acrylic vs Sapphire Inserts

[springer]

GMT-MASTER BEZEL INSERTS FOR THE 1675/16750 AND 16760/16710/16700 MODELS

There are two variations of bezel inserts for the discontinued GMT and GMT II models:

1) Acrylic model inserts (GMT 1675 & 16750)
2) Sapphire model inserts (GMT 16700, GMT II 16760 and 16710)

The inner and outer diameters are different for both types of inserts. Normally, when measuring an insert, they will not measure exactly to these dimensions due to age, stretch or other factors.

1) Acrylic: 1675/16750
Inner Diameter: 30.2mm...... Outer Diameter: 37.75mm

2) Sapphire: GMT II 16760/16710 GMT 16700:
Inner Diameter: 30.7mm...... Outer Diameter: 37.63mm

If you know the subtle differences between the acrylic and sapphire inserts when viewed from the back, it becomes very apparent whether a GMT insert fits an acrylic or sapphire model.

The sapphire inserts will fit on the 1675/16750 acrylic crystal models – especially if the insert is flattened out a little with the help of a wooden dowel or other item. The bezel will spin freely when installed - even though the inner diameter is slightly less with the sapphire insert than an acrylic insert.

I have placed several photos here depicting the differences between the acrylic inserts (1675/16750) and the sapphire crystal inserts (16760/16710/16700). When viewed from the back, the acrylic inserts have a very thin ring on the outer edge. The sapphire inserts have a thicker outer ring when compared to the acrylic inserts along with a middle ring. When viewed, the sapphire insert appears to have three distinct rings on the back while the acrylic insert appears to have two distinct rings.

In the photos below, I have included a GMT 16750 that has a sapphire insert fit to the bezel and installed on the watch. It fits tight and the bezel turns freely.

[Frogman4me]

Great info John. Thanks for posting.

[lee fowler]

Thanks John makes interesting reading.

[nachifisio23]

Great reading, thanks for sharing.

[Loevhagen]

Very useful.Thanks.

[JohnBaker3]

Thanks John!

As usual, good stuff to know about our beloved GMT's...

[RC2]

John. Never knew that. I should not have sold David my 16710 insert! Lol

[nycpassat]

Great info and resource John!

[linesiders]

Sapphire insert fits the plexi watch, spins, and makes you fear it will pop out when least expected

[springer]

Originally Posted by linesiders

Sapphire insert fits the plexi watch, spins, and makes you fear it will pop out when least expected

Only ebayers use sapphire inserts on the acrylic models!!!

[eliwise]

Any thoughts on official colors versus aftermarket? I have a humble collection of about a dozen or so inserts for my 1675/3.
-Black / Gold (Thin font, medium font, fat font)
-Root Beer in several / various stages of fading
-Brown / Gold various (seen on the all gold 16758)

[springer]

Originally Posted by eliwise

Any thoughts on official colors versus aftermarket? I have a humble collection of about a dozen or so inserts for my 1675/3.
-Black / Gold (Thin font, medium font, fat font)
-Root Beer in several / various stages of fading
-Brown / Gold various (seen on the all gold 16758)

I can't help you there - I am not very knowledgeable with the 14K/SS two-tone GMT inserts. There are several other threads on the forum regarding bezel inserts which might address your concerns. My intent here was to provide photos and commentary that would allow a casual collector to identify a particular GMT insert based on its size and appearance and make an educated guess as to whether it fit an acrylic or sapphire model. I see inserts incorrectly identified much too often and hopefully this will save some of the good members here from any issues regarding a future purchase or aggravation with a poor fitting insert.

[JustinK]

Great info Springer!

Have you run into older fat font inserts with a notch in the back? I have seen more than a couple like this and have always assumed this was done to make them easier to insert in the bezel. I am not sure if they came from Rolex like this or if the notch was done by a watchmaker. Any thoughts?

[springer]

Originally Posted by JustinK

Great info Springer!

Have you run into older fat font inserts with a notch in the back? I have seen more than a couple like this and have always assumed this was done to make them easier to insert in the bezel. I am not sure if they came from Rolex like this or if the notch was done by a watchmaker. Any thoughts?

I've never seen a notched insert but it very well could have been done by a watchmaker.

[JustinK]

Here are two inserts with the notch however I know I have owned others. I can't say I have seen notches on pepsi or black inserts.

[linesiders]

Originally Posted by springer

Only ebayers use sapphire inserts on the acrylic models!!!

Hehehe - so many mislabeled, so little time. I had someone swear my up and down one was for plexi when it was clearly sapphire

[morafa4]

Great write up, Springer! Any chance we can get a picture of the reverse side of the batch of red-back inserts you posted?

Originally Posted by springer

GMT-MASTER BEZEL INSERTS FOR THE 1675/16750 AND 16760/16710/16700 MODELS

[springer]

Originally Posted by morafa4

Great write up, Springer! Any chance we can get a picture of the reverse side of the batch of red-back inserts you posted?

They are on here somewhere.... Can't tell you for sure, but have a look anyway.

[springer]

Originally Posted by JustinK

Here are two inserts with the notch however I know I have owned others. I can't say I have seen notches on pepsi or black inserts.

I have never seen those notches before. Sorry I can't help you out more.

[linesiders]

I have had 20-30 1675 Fat and Mid font inserts, have never seen that mark.

[JustinK]

I think the notch might be present only on some of the TT inserts. Here is another one I just saw on Ebay.

http://www.ebay.com/itm/Vintage-Role...r4JXbLts-Sjdww

[TimeToGo]

Originally Posted by JustinK

I think the notch might be present only on some of the TT inserts. Here is another one I just saw on Ebay.

http://www.ebay.com/itm/Vintage-Role...r4JXbLts-Sjdww

That is interesting.. So far common with Root beer inserts..

[southtexas]

Originally Posted by JustinK

I think the notch might be present only on some of the TT inserts. Here is another one I just saw on Ebay.

http://www.ebay.com/itm/Vintage-Role...r4JXbLts-Sjdww

I had one like that also, not sure what it's for?

[JustinK]

Originally Posted by southtexas

I had one like that also, not sure what it's for?

My guess is to make the insert more flexible so it's easier to install. I have been looking for this notch on other inserts but have not seen it on anything other than the root beer. It was probably a certain supplier that did this for a batch of inserts.

[SLS]

Thanks for the write up John. Is there any way to determine that an insert is not original Rolex? Or is it just becoming familiar with the tell tale signs of aftermarket inserts. Thanks,
Scott

[shou.biao.kuang]

Never cease to learn new things from you all the times

[springer]

Below are some photos of an aftermarket insert along with a couple genuine inserts for comparison. This aftermarket insert is the most common variety and is referred to as the "hooked 2" due to the excessive outward hook found on the top loop of the 2s.

[Gimoozaabi]

Bumping this excellent thread. I used it as a reference when buying a black insert for my 16710. Thanks Springer!

[TimeLord2]

Yea, I love this thread, very useful. Thank you so much for taking the time to put this together.

[strafer_kid]

Yes - really excellent reference.