Bulova 1920 -Unknown
2 piece Case measures 27.5mm lug to lug x 19mm non inclusive of the Crown using Calipers.
Unsigned Dial shows Black printed Arabic numerals.
Hour and Minute Hands are Fusaux style.
Movement bridge is Hand signed Bulova, plate is stamped Tissot.
Hinged Caseback is stamped as shown.
Date of manufacture is speculative.