U boat watch classico 45 gmt 45 beiridescent effect 8051u boat watches understands perfectly the meaning ofinnovation always passioned about advanced and unusual techniques and materials italo decided to apply under the thick and scratch proof sapphire glass of thenew u boat watchesclassico gmt a thin layer ofanatolite the most effective existing colour change gemunique and rare this special stone acquires different colors when viewed under different lights the ability tochange