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Omega 251

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Omega 251 caliber

Omega 251 caliber

Basic Information

Name	Omega 251
Manufacturer	Omega
Launch Year	1938
Caliber Family	Description no second: 240 (R13.5 until 1949): 15 jewels 241: 15 jewels, antimagnetic 242: 17 jewels 243: 17 jewels, antimagnetic 244: 17 jewels, antimagnetic, Incabloc 245: ring balance 19800 A/h instead of screw balance 21600 A/h sweep second: 250 (R13.5SC until 1949): 17 jewels 243(251): 17 jewels, antimagnetic 252: 17 jewels, antimagnetic, Incabloc Related calibers Omega 240, Omega 241, Omega 242, Omega 243, Omega 244, Omega 245, Omega 250, Omega 251, Omega 252, Omega R13.5, Omega R13.5SC
Is COSC certified	No

Technical Details

Lignes Dimensions	5.98 ‴ x 7.98 ‴
Dimensions	13.5 mm x 18 mm
Height	4.15 mm
Further Measures	Mounting Diameter (Dm): 13.5 x 17.5mm Stem height (T): 1.6mm Mounting Height (F): 0.8mm
Power Reserve	48 hours
Frequency	21,600 vph
Jewels	17
Lift Angle	59 degrees

Complications and Specifications

Shape	Cushion
Complications	Sweep Second
Shock Protection	Incabloc
Regulator Type	Pinned Regulator (or Index Regulator)
Movement Type	Manual
Escapement Type	Swiss Lever
Control Type	Balance Wheel
Winding Type	Stem Winding (Crown)
Setting Type	Stem Set (Crown Pull)

Additional Information

Hand Sizes	1.10 x 0.70 x 0.15mm
Hand Count	3
Country Of Manufacture	Switzerland
Notes	Remarks: 1938-1959, >1400000 (whole family except 245) Other data: balance staff: U1603 stem: W1298 mainspring / battery: 1.20 x 6.5 x 0.08mm balance staff ronda: 1846 (6 x 8) stem ronda: 670 (6 x 8) stem ronda: 132 (6 x 8) Mainspring: 1.200 x 6.500 x 0.080 x 200.000 mm
Signature	1961: 17825778, Omega Watch Co Swiss, 17 Jewels; Incabloc (Omega 252)
Import Codes	OXG — Norman Morris imports, Omega (1937 - 1970), Ollendorf Watch Co.

Metadata

Created At	Sep 15, 2023
Updated At	Apr 23, 2025, 11:33:38 PM