Rolex 4161

Regatta chronograph movement for the Yacht-Master II, introduced at Baselworld 2013. Based on the Daytona's 4130 with programmable countdown timer that can be set from 1-10 minutes for regatta race starts. Features mechanical memory and on-the-fly synchronization. The bezel works in conjunction with the movement - rotating 90 degrees locks/unlocks the countdown function. Uses UV-LiGA micromanufacturing technology for components too small for traditional machining.