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FEF 380

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Basic Information

Name	FEF 380
Manufacturer	Fabrique d'Ébauches de Fleurier
Launch Year	1950
Caliber Family	Description 350: 10.5" 380, 381: 11.5" 380-2: 11.5" , date Related calibers FEF 350, FEF 380, FEF 380-2, FEF 381
Is in house development	No
Is COSC certified	No

Timegrapher

Beat rate

18,000 bph

Frequency

2.5 Hz

Reference: healthy amplitude ≈ 270–315° fully wound (>200° at 24 h); beat error ideally < 0.5 ms.

Technical Details

Lignes Dimensions	11.5 ‴
Dimensions	26 mm
Height	4.5 mm
Further Measures	Mounting Diameter (Dm): 25.6mm Stem height (T): 2.1mm Mounting Height (F): 1.5mm
Power Reserve	41 hours
Frequency	18,000 vph
Jewels	17

Complications and Specifications

Shape	Round
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	1.50 x 0.90 x 0.20mm
Hand Count	3
Country Of Manufacture	Switzerland
Notes	Remarks: early fixed, later mobile stud carrier differences not known between 380, 381 Other data: balance staff: U1463 / U3096 balance with/without screws stem: W1174 mainspring / battery: Zf1129, 1.45 x 9.5 x 0.105 x 300mm balance staff ronda: 957 (11,5) stem ronda: 208 (11,5) Ranfft mentioned about this caliber: There are variants with this quantity of jewels 15, 17
Signature	ca. 1950: Swiss, 17 Jewels - FEF 380; Incabloc

Compatible Parts

No parts linked yet for this caliber.

Metadata

Created At	Sep 15, 2023
Updated At	Apr 23, 2025, 11:32:26 PM