Patent ID: 8920518

Claim:
A vacuum liner for use with a prosthetic device to be secured to a residual limb, the vacuum liner comprising: an elongated elastomeric tube having a closed distal end and an open proximal end, and defining an interior liner space configured to receive the residual limb; the closed distal end including a distal portion formed of a higher durometer elastomeric material than surrounding portions of the elastomeric tube; wherein the distal portion defines a disk shaped protrusion having a perimeter and includes an exterior liner space defined by a recessed concave surface formed by a depth into the higher durometer elastomeric material, the recessed concave surface extending from an external end-surface of the distal portion adjacent to the perimeter and towards the interior liner space; wherein the distal portion is sized and configured for mating against a surrounding socket so that as weight is applied to the socket, the exterior liner space collapses due to applied weight and forces air contained out of the socket, when weight is relieved from the socket, the higher durometer elastomeric material of the distal portion is urged to return to its original shape, pulling air into the exterior liner space from the surrounding socket.