Cartie, Ballon Bleu de series, model: WSBB0039, automatic movement, stainless steel, case diameter: 40mm, black alligator leather strap, paired with stainless steel clasp, arched convex sapphire crystal cover, concealed design (not transparent), silver-gray radial pattern guilloche dial, black Roman numeral hour markers, blue steel sword-shaped pointer, 3 o'clock position date display window, side hidden convex crown, set with synthetic corundum sapphire beads, is the signature symbol of the Blue Ball series.