Grey balance wheel part for Hublot, Jacob and co, Romain Jerome and other tourbillon watches whose movements were manufactured by BNB manufacturer in Switzerland. Very rare tourbillon watch part, and unused. Perfect replacement. Please note the pictures of watches are shown as an example. You are buying just the grey balance wheel for a similar tourbillon watch or movement. See my other listings for a gold version of this tourbillon balance wheel, and also tourbillon cage parts. Best!
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