The center hole is sized specifically to the maker world clock kit and mounts to the hour hand mounting spot on the clock motor and is a press fit. The hand mounts where the face normally mounts with the supplied washer and nut.

The face rotates instead of the hand, and keeps time accurately. The clock movement has to be modified to run backwards. Check out my other uploads for a basic wall version and desk version.

The rotating face clock is my original design and unless I have it on my page, it is an unauthorized copy.