Caliber UR-7.30

The calibre of the UR-230: three rotating cubes on a carousel each carry four hour numerals, and a 3D retrograde hand escorts the current hour along a 120-degree minute track before flying back to zero. It has two sets of turbines, one to absorb external shocks and one to govern the air flow that feeds the winding, and a control on the back disengages the rotor entirely so the watch is wound by hand. Automatic, 4 Hz, 48 hours from a single barrel, 50 jewels, on an ARCAP P40 baseplate. URWERK's releases call it developed by URWERK without saying who makes its base.