Limited edition u boat watch classico 48 phoenix limited edition with cracks that have been patiently filled by italian craftsmen at the u boat factory the u boat classico 48 phoenix limited edition is a limited edition piece which features a mother of pearl dial its 48mm case has received a martellee finishing which has been partially drilled to allow for small cracks to appear in its 826 sterling silver case each crack has been filled with exquisite black diamonds with strong brand ident