On the Breguet web site, Ref 5237 is listed as 37mm x 10.65mm. There is an older version of this watch, which I believe is also called Ref 5237. The easy way to tell them apart is that the new one has a yellow gold dot at 3 and 9, while the old one has the cutoff romans.
My question is whether there are any movement differences (improvements, etc.) and if the case size is the same.
thanks
Felipe