How common was it for watchmakers to make the same movement in multiple sizes? I don't recall seeing any cases of this until recently. The dramatic example is a pair of signed-C.H. Meylans. I collect C.H. Meylans. I have classified the movement type in these examples as a Type F (see Dropbox - C.H. Meylan Serial Number Database.doc - Simplify your life), which I understand to have been made or based on an ebauche made by Louis Elisee Piguet, which many Swiss firms also used. As you can see, Type F came in at least two sizes, men's size (42mm cased) and ladies' size (25mm cased). I have quite a few men's-sized Type Fs, but I only just acquired the platinum-cased example shown. It is next to a typical men's-sized Type F. Both movements were adjusted to 5 positions. The little one has one more jewel than the big one, 19 jewels. The insignificant example also consists of two C.H. Meylans that used LeCoultre Kaliber 6 movements or ebauches, Type B in my classification scheme. I recently bought a Type B from which to pilfer parts to repair another Type B. Alas, the two movements were slightly different sizes. The parts were not interchangeable. If you have examples of big and little siblings, please post them.