Otsuka Lotec, a highly popular Japanese watch with an extreme industrial style, has recently gained popularity

The unique feature of Otsuka Lotec No.5 KAI lies in its self-made star wheel hour module,

Composed of 3 rotating disks, each representing 4 hours, driven by the central rotating disk.

The hour dial is driven by a double reduction gear and moves on a 120 degree curved track every hour, accurately indicating the time.

To prevent backlash in the star wheel mechanism, a double reduction gear system has been specially designed,

Meanwhile, two Japanese made ball bearings from Minebea Mitsumi can be seen on the dial.

One of them is used to drive the hour disk, causing it to switch instantly twice per hour, like a time jumping device; The other one is located at the center of the second disk, with a diameter of only 1.5 millimeters,

It is the smallest bearing of its kind in the world, adding a unique technological charm to watches.

40.5mm diameter