Ebauches SA, 475B, P2-V2 Prototype, July 1959
Category: functional prototype, aesthetic prototype
Description: Asymmetrical, gilt brass cased prototype. Stainless steel snap back with factory engravings. Two round protrusions on the left of the main case, one containing a battery, one with space for a back-up battery. White dial with raised, silver coloured, fancy 15min indexes, black printed 5min indexes. Black printed ‘Electric’ under ’12, ‘Swiss Made’ below ‘6’. Blue printed ‘475 B’ above ‘6’. Gold coloured hour and minute hands, black seconds hand with lightning symbol tail. Gilt metal crown.
Dimensions: 51.5mm (without crown), lug width: 19mm
Movement: 475 P2 Prototype movement, unumbered
Additional info: This piece represents one of the two versions of the second iteration of the first Swiss made battery driven wrist watch prototypes. The caliber identification is set and named 475. This is the second variant (V2) of this caliber, being alimented by one, small ‘normal’ battery. This version was vulgarly nicknamed ‘montre a cuilles’ in French, which would translate as ‘watch with balls’, because of the distinctive round housings of the batteries.
As mentioned in the parent section, one other version of the same caliber would be alimented by a big rechargeable battery located in the back of the bi-parted case back.
Interestingly the case back is stamped with the manufacture date 7/59 and this info is repeated on the outside, where it is hand scratched. The next generation of prototypes (P3) will be of the aesthetic group and will already feature the definitive caliber L4750.
Provenance: Ex Hans Baumann collection
Published:
Bramaz H.-R., Baumann H.; Die Elektrische Armbanduhr, Band 1, Verlag Stutz Druck AG, Wädenswil, 2013
Mazarian C., Collection Electrique, Editions Chène, 2024, ISBN: 2812321628 – French (see also Italian and English editions)
Electric Watch Prototypes 