"The Calibre 3100 Twin Date becomes more worldly as the Eco-Drive Perpetual Calendar with Twin Date proudly features a World Time Dial Ring operated by a second crown. Stainless Steel Case and Bracelet with Gold Tone Accents Mineral Glass Crystal Water Resistant to 100 Meters (330 Feet) World Time Dial Ring Perpetual Calendar Large Double Date Window at the 12 o'clock Sub-Second Dial 12/24 Hour Dial Bracelet features a Double Hidden Push Button Release Fold Over Clasp 1 Year Power Reserve when fully charged (230 Hours to fully charge with average lighting) 43mm Case Width (Approximately 1 5/8"")"