Junhans J31
- Kind:
- Indestructible Watch
- Production:
- 1923
- Type:
- Open face
- Variants:
- J31
- Catalog Group:
- 102
- Size:
- 18,5"
- Outer Diameter:
- 42,0 mm
- Nominal Diameter:
- 41,4 mm
- Height:
- 6,8 mm
- f:
- 18000 A/h
- Power reserve:
- 40h
- Balance staff:
- U418
- Stem:
- W300
- Mainspring:
- 2f3641
Junghans mentions spring #1007
450 x 2,25 x 0,205 mm - Reference picture:
- F.W.S 1942 page 17
- Jewels:
- 3
Although we commenced watch manufacturing at a comparatively recent date our watches have already, owing to their high quality and reliability, gained a world-wide reputation. Our method is: Utmost precision in the production of all parts, ruthless removal and destruction of all parts which are found to be in the least faulty or inexact, assembling, examination and regulation by proved experts. This system ensures equal high quality of all our watches and absolute interchangeability of all parts.
Page 12
Indestructible Watch
Watch movement No. J31 well regulated.
3 jewels, compensating hair spring, club teeth escape wheel, double safety roller, gilt plates.
Page 15
Movement No. J31 with 3 jewels, compensating hair spring, club teeth escape wheel, double safety roller, gilt plates.
Case: White metal or silver with gilt rim 0,800
Dial: White enamel dial with or without Radium luminous figures (RZ)
Bow and crown: If white metal case: white metal
if silver case: galonné or gilt.
102/1 18 1/2''' - White metal plain
102/2 18 1/2''' - White metal engraved
102/3 18 1/2''' - White metal engraved and with gilt rim
102/4 19 1/2''' - White metal plain
102/5 19 1/2''' - White metal engraved
102/30 18 1/2''' - Silver with gilt rim 17gr., Inside dome of metal
These watches can also be supplied with Radium luminous figures (RZ)
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