Reboot your retro style with the Casio CA-53, a modern take on the iconic Casio Mini calculator from 1972. This watch honours the original design, featuring a calculator-style LCD display and full keypad, with green text on a negative LCD and red mode indicators, all reminiscent of the Casio Mini’s groundbreaking look. Beyond its nostalgic design, the CA-53 offers practical functions, including a calculator for basic arithmetic, dual time, a stopwatch, and an alarm. The bio-based resin band helps reduce environmental impact. The Casio Mini, released in 1972, was the world’s first personal calculator, revolutionizing technology with its compact size and affordability. It sold six million units and earned a spot in Japan's National Museum of Nature and Science as an Essential Historical Material for Science and Technology. - 43.2 × 34.4 × 8.2mm Case Size - 25g Weight - Resin Case and Bezel Material - Bio-based Resin Band - Water Resistant - Approx. battery life: 5 years on CR2016 - Resin Glass - World time: Dual time - Stopwatch - Alarm/hourly time signal: Daily alarm - Calendar: Full auto-calendar (to year 2099) - Mute feature: Button operation tone on/off - Accuracy: ±15 seconds per month - 8-digit calculator - 12/24-hour format - Regular timekeeping: Hour, minute, second, am/pm, year, month, date, day