Fonderie 47

Inversion Principle Timepiece

Inversion Principle Timepiece
Inversion Principle Timepiece
Inversion Principle Timepiece
“We set out five years ago to create an original mechanical timepiece from an AK47. A piece that would reflect the finest Swiss watchmaking traditions and embody our principles and our mission of change; all at the same time. This was no easy task, but thanks to a remarkable team, I think that we well and truly have achieved this aim. But then, Inversion Principle also is more than just a watch. It is a manifestation of the principle that anything is possible.”

– Peter Thum, CEO and Co-founder

Purchase the Inversion Principle Timepiece

$ 195,000.00

A completely original timepiece, Inversion Principle features jumping hours, retrograde minutes, and a 3-minute tourbillon. Designed by Adrian Glessing and produced by David Candaux, it is a limited edition of 20 pieces: 10 in white gold and 10 in red gold.

Bears the serial number of the AK47 from which the steel was wrought.

Purchase enables the destruction of one thousand assault rifles in Africa.

Delivery currently is running about 8 weeks from placement of order and selection of case color.

This item will be delivered by secure courier by hand. Select any FEDEX option to place your order.  This step will be revised personally with the client.

Please email us here if you want to initiate the purchase of the watch:

$ 195,000.00

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Inversion Principle is a completely original timepiece, designed by Adrian Glessing and developed by David Candaux/Du Val Des Bois exclusively for Fonderie 47.

The sale of each timepiece funds the destruction of one thousand assault weapons in Africa, creating a safer environment for aid and development.

First and foremost, Inversion Principle is a very exclusive haute horlogerie timepiece, with subtle elements and mechanisms that discreetly feature key attributes of the AK47. Each timepiece incorporates a plate on the back made from the transformed steel of a destroyed assault weapon.

The central 3-minute flying tourbillon dominates the three-dimensional dial. Three second-hands, equally spaced 120° apart around the tourbillon cage, arc across the seconds-scale above the tourbillon and 'Fonderie 47': The tourbillon revolves at just 1/3 of the speed of a traditional tourbillon. Only one second-hand is visible at any time − the other two are hidden under the gold rifle-sight inspired frame set into the sapphire crystal.

Gun mechanisms snap sharply and precisely into place: As does the instantaneous jumping hour at 12 o'clock as it changes the hour; and the large 240° retrograde minutes hand as it flies back to zero each hour across the bottom of the dial. Each press of the quick-set pusher in the crown advances the jumping hours by one hour.

The long 6-day power reserve has both a lateral indication via a sapphire window set into the left side of the case band and a second indication visible through the display back.

The display back reveals the stunning sunray guilloche pattern radiating out from the ratchet wheel, which is capped by a dark plate of transformed steel from a destroyed AK47. The plate is in the form of the Fonderie 47 brand symbol and rotates as the watch is wound. '56-3701F42', the serial number of the destroyed weapon the metal is from, is elegantly hand engraved beside the plate.

Technical Specifications


Limited edition of 20 pieces: ten 18k white gold, ten 18k red gold; central three-minute flying tourbillon; instantaneous jumping hours; 240° retrograde minutes; central seconds from tourbillon cage; crown pusher quick-set hour adjustment; six-day power reserve with both lateral and back indications; metal from transformed assault weapon.


Jumping hours, 240° retrograde minutes; central seconds on tourbillon cage; lateral power reserve indicator on case band and power reserve indicator on back.

Case and Strap
Material: 18k red gold or 18k white gold
Sapphire crystal traversed by embedded gold bezel bridge framing tourbillon cage
Lateral sapphire window in case band for power reserve indicator
Dimensions: 42mm x 14.6mm
Water resistance: 30m/100’/3ATM
Dial: Translucent glass and sapphire crystal with enameled minutes and seconds
Strap and clasp: hand stitched alligator strap with gold pin buckle matching case. Brown leather with red gold case or black leather with white gold case
Created by: David Candaux/Du Val Des Bois
Designed by: Adrian Glessing
Place of Manufacture: La Vallée de Joux, Switzerland
Caliber: F47-001
Regulator: central three-minute flying tourbillon
Tourbillon cage: gold counter weight and curved to follow sapphire crystal
Jumping hour: thin mechanism (patented)
Retrograde seconds: mechanism with light aluminum arm and precision regulator
LIGA plate: platform for tourbillon and fixed seconds wheel by Mimotech
Power reserve: six days
Balance frequency: 18,000bph (2.5Hz)
Balance spring: Breguet overcoil and distinctive balance spring stud
Jewels: 38
Steel plate from transformed AK47 − serial number '56-3701F42' − in form of Fonderie 47 brand symbol on ratchet wheel visible through display back.
Finishing: Sun ray guilloche; hand engraving; hand polished bevels; heat-blued screws and power reserve indicator on back