The watch has the highest grade Invar caliber movement , lever chronometer , precision regulator,old style hand engraved balance cock,Invar balance,Breguet spiral,maximum jeweles. Invar was invented in 1896 by Swiss physicist, Charles Edouard (acute on 'E') Guillaume, but he was only internationally recognized for the discovery in 1920 when he received the Nobel prize for physics, encouraged by the improvement in scientific instruments that the use of Invar had allowed. Invar has proved to be an incredibly useful alloy and is used where high dimensional stability is required, such as precision instruments, clocks, seismic creep indicators, TV shadow-mask frames, valves in engines, and antimagnetic watches. I have not so far mentioned the useful antimagnetic properties of Invar, but in comb.
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