Blancpain 'Tribute to Fifty Fathoms' MIL-SPEC (Water-Tightness Indicator) 40mm Stainless - Ref# 5008-1130-B52A. Released at Basel 2017 as Special Edition of only 500 Pieces, this model is the predecessor to the Hodinkee 40mm Fifty Fathoms MIL-SPEC.
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