Inside case back: Bulova Quality Pat June 10, 1924 Outside case back: nothing Dial etched silver w/ small round register compared to overall dial size. Says: Bulova {stamped} Siwss Mvnt: 6AF Swiss Bulova Watch Co. 15 Jewels, sn 239242 Case measurements: case only, not counting wire lugs 27.7mm x 16.7 (not counting crown) case height from wire lug tip to tip 32.0mm Crystal: acrylic raised, tonneau 21.7mm x 11.6mm measured in case at bezel interface
My '43 G-S catalog has a T683 that appears to match the dimensions but is only listed for ACME, no mention of Bulova. Also, Princine isn't mentioned in the index. The '30 G-S catalog doesn't have any that are close. So far I'm unable to cross-reference to another crystal brand as I'm lacking catalogs from the '30's.