Prostheses that are controlled to a low pressure for the amputee comprises a single socket having a volume and shape to receive a substantial portion of the residual limb. Liner having less capacity than the remaining limb is placed over the residual limb, the liner is extended to the overall contact relationship with the residual limb. Sealing cavity is formed between the socket and the liner. The vacuum source is connected to the socket cavity, whereby the residual limb and the liner, pulling the stable, and full contact with the socket. To compensate for air leakage past the seal, there is a mechanism for holding the vacuum in the cavity. Osmosis membranes, wrap the residual limb, and make a space between the residual limb and the liner. Osmosis membrane, in only one direction, ie toward the liner from the residual limb, to allow the passage of water. Vacuum may be added to the space between the permeable membrane and the liner in order to assist in discharging the sweat from the residual limb.