A device includes a first partial, circular shroud which includes an upstream shroud portion and a downstream shroud portion; an upstream slot panel, defining an upstream bypass slot, disposed on the upstream shroud portion; and a downstream slot panel, defining a downstream reentry slot, disposed on the downstream shroud portion. According to one embodiment, an upstream dam is disposed on the upstream shroud portion, and a downstream dam is disposed on the downstream shroud portion. Upstream and downstream slot fins may be integrally formed with the respective upstream and downstream slot panels, extending radially outward from the respective portions of the shroud. A diverter is disposed on the upstream shroud portion, substantially between the first upstream dam and the upstream bypass slot, extending radially inward therefrom, in one embodiment. A separator plate is disposed on an intermediate portion of the shroud, extending radially inward therefrom, in one embodiment. As one example, the device is useful for manipulating flow associated with a spinning disc, such as in a disc drive.