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Replacement watch crystal?


Registered User
Jul 31, 2008
Hello All,

I've got a Waltham model 870 in a Wadsworth case. The crystal appears to be 22.86mm by 20.32 mm domed rectangular crystal. However, this is measured with the crystal in place so it may be off a bit.

I've read some guides that say there is a number stamped into the case that indicates the replacement crystal, but I can't find it.

I'd rather not order 100 crystals and test fit them all.

Any suggestions?



Registered User
Dec 28, 2010
So. Cal., USA
I ended up buying 4 different round mineral glass crystals for a friend's watch after measuring with the old crystal in place. If you don't want to take it to a watchmaker, you might seriously consider removing the old crystal and measuring it (providing it's glass and a good fit) and the bezel before placing the order. If you do order slightly large though, you should be able to reduce the large dimension enough to fit well. Straight sides are probably a bit easier to do this with.

In the round watch I ordered 4 crystals for, I could have ordered 5, as I had to reduce the diameter slightly due to my neglecting to order the perfect size. Either this, or take it to the watchmaker as was suggested. Good luck.