In 1990 at the Basel watch fair, IWC unveiled their very first 'Grande Complication' wristwatch. They used the foundation of Kurt Klaus' perpetual calendar module and then took it a step further by incorporating a minute repeater into the intricate movement. The case was a significant 42.2mm wide and 16.3mm tall, making it quite large for its time. The reference IW3770-01 boasts a platinum case and a silver and white dial with German markings.