Creating Jewish timepieces Konstantin Chaykin was inspired by the complexity and astronomical precision of the Jewish calendar. The Jewish people use this calendar for religious purposes throughout the world; it is also the official calendar of Israel. Decalogue movement invented and created by Konstantin Chaykin turns hands anti-clockwise. This feature is called the reverse movement system of the minute (pointer) wheels, is a patented invention by Konstantin Chaykin. The Decalogue is a genuine Jewish watch featuring manual winding, an anchor escapement, a shock-absorber and an additional moon-phase display.
The Decalogue Rega is a more complex version of the Decalogue and is the only timepiece in the world to count Jewish units of time: halakim and regaim. These short units of time have been known to Jewish sages since ancient times; here, for the first time, they are embodied in a wristwatch. Together with 24-hour periods and hours, they form the basis for timekeeping in the Jewish calendar. A helek ('a part' translated from Aramaic) is 31/3 seconds, while a rega is just 44 milliseconds. Rega is thus the smallest unit of time. Its synonym in Hebrew, haref ain, means 'the twinkling of an eye'.