Omega Balance Complete Ref 721

Calibers 38.5T1 17”’ 18”’ 19”’ 244

Omega Cal: 38.5 was introduced in 1932 with 15 or 17 jewels, renamed to cal 160 in 1953 when it became Antimagnetic. Production ended in 1966.

Data Omega 161 (38.5T1 AM 15P).

• 15 jewels, manual wind, hour, minute, sub second.
• Size: 38.50 mm.
• H: = 4.95 mm.
• N: = 18.000 A/h.
• Power reserve: 42 h.
• Mainspring: 2,10 x 15 – 0,18 – 450 mm

Omega, prior to 1894, was Louis Brandt & Frère – a watch company based in Bienne, which produced watches, prior to the adoption of the Omega name, under a variety of different brand names, including Jura, Patria, and Helvetia. In 1894, however, the company began production of a movement that was to change watchmaking history, and whose name was to become established as one of the most important in the history of Swiss watchmaking. This movement was the Omega caliber – a 19‴ ( 19 ligne )

Data: Omega 18”’ LOB

• 15 jewels, open face caliber, sub second.
• Size: 18”’ 40.61 mm.
• H: = 6.65 mm.
• N: = 18.000 A/h.
• Power reserve: — h.
• Mainspring: 1,80 x 15 – 0,18 – 460 AT = Double brace and hole.

Data: Omega 19”’ LOB

• 15 jewels, open face caliber, sub second.
• Size: 19”’ 42.7 mm.
• H: = 6.55 mm.
• N: = 18000.
• Power reserve: 38 h.

Data: Omega 244 (R 13.5 PC AM 17 p)

• 17 jewels, manual wind.
• Size: 17.50 x 13.50 mm.
• H: = 3.25 mm.
• N: = 21 600 A/h.
• Power reserve: 46 h.

Versions:

• R13,5: until 1949, 15 jewels (1939).
• 240: after 1949, 15 jewels (1949).
• 241: 15 jewels, antimagnetic (1949).
• 242: 17 jewels (1944).
• 243: 17 jewels, antimagnetic (1950).
• 244: 17 jewels, incabloc (1950).
• 245: 17 jewels, flat balance ring, 19800 A/h.
• R13,5SC: until 1949, 17 jewels, center second (1940).
• 250: after 1949, 17 jewels, center second (1949).
• 251: 17 jewels, antimagnetic, center second (1950).
• 252: 17 jewels, antimagnetic, center second, incabloc (1951).