The Arca-Swiss TopPan fits in between the aspherical ball and the camera mounting plate, and provides a second panorama panning base, independent from the angle of ballhead. This is very handy for when the tripod is not on level ground. The need for laborious readjustments has thus been made redundant.
Moreover, on the Monoball B2 with its two directionally independent ball movements, the camera configuration can be continuously swiveled around its horizontal axis at 90° tilting angle and correspondingly leveled.