Bulova 1965 Ambassador

Bulova Ambassador 30 Jewel micro-Rotor 12EBA 10KTg.f. M5/M4

Case Dimensions and features:

• Width w/o Crown:   33.55 mm
• Length:   36.40 mm
• Depth:   4.15 mm wo/crystal, 9.30 mm w/crystal
• Lug Width:   17.15 mm
• Crown:   5.45Dia mm, unsigned (appears to be a service part)
• Crystal:   30.40Dia mm, in bezel.  Shallow Domed Acrylic
• Bezel O.D.:  33.25 mm
• Dial O.D.:  29.95 mm
• Inside case back inscriptions:   A faint watchmaker inscription
• Outside case back inscriptions:  10KT Gold Filled; Bulova; M5; I333107

Movement:

• 12EBA Automatic Micro-Rotor 30 Jewel, No Date
• Engraving on Movement:  BULOVA  WATCH CO; 12EBA; 30 Jewels; Swiss; M4.
• Movement Diameter: 28.55 mm

Notes:  One of a number of micro-rotor Ambassadors I own.  The date code on the outside of the case is M5, and the date code on the movement is M4.  In my opinion it was likely produced in 1965.  I have seen this mismatch frequently with vintage Bulova.  Generally it is consecutive years, but occasionally the gap is more than a year.