US Patent 11306831 Relevant to taps and handles and their operation

A tap assembly includes a flow control mechanism, a spindle which rotates about its principal axis to operate the flow control mechanism, and a handle connectable to the spindle. The location on the handle where the spindle connects coincides with the spindle's principal axis but does not with the centroid of the handle's planform shape. When the handle is turned by a user, the handle rotates about the spindle's principal axis. The handle also moves or translates relative the spindle's principal axis. When the handle is in an initial “fully off” position, there is an area that is obscured from a user's view by the handle, but when the handle is initially turned from the initial position towards a final “fully on” position, the area begins to be revealed, and with further rotation of the handle towards the final position, more of, or different parts of, the area become revealed.