A system for the contactless sealing of a rotatably mounted shaft with respect to a housing, and a gear unit, oil being provided in the interior of the housing, in particular, the rotating shaft protruding from the interior into the outer area; a centrifugal disk, joined in rotatably fixed manner to the shaft, having at least partially radially extending bores that connect oil from a centrifugal chamber to a collection chamber surrounding the centrifugal disk.