<p>The device has a sealing body to seal a fastening body (3) in a mounting hole (2) of a housing. A sheathing body (1) made of elastic material/metal extends between the sections of the fastening body and the hole. The axial and radial distances between the sections are bridged in a fluid sealing manner by the axial distance between the installation points of the sheathing body and the pretensioning force of the sheathing body. Channels (16-18) are provided for hydraulic fluid. Connection between channels (16,17) are controlled by an electromagnetically operated closing member (8).</p>
