The Glash:utte Original Senator Perpetual Calendar is a perfect balance of complexity and simplicity. Its caliber 100-02 movement powers the perpetual calendar, and its various indications can be easily seen through the dial's apertures. These include the iconic 'big date' window and a subtle leap year indicator. The watch comes in three variations, with a rubber strap and either a pin buckle or folding clasp. Whichever reference you choose - 100-02-22-12-06, 100-02-22-12-04, or 100-02-22-12-53 - you'll have a stunning timepiece on your wrist.