This Ulysse Nardin Marine Acqua Perpetual takes the Marine line in a more technical direction, pairing a stainless steel build with a perpetual calendar. The 43mm case and matching steel bracelet give it a solid, sporty feel, and the black dial keeps things straightforward. Its automatic movement combines the perpetual calendar with a date display for useful complexity. On the wrist, it has broad, modern proportions and a clear maritime identity.