A prosthetic device includes a first place including a first end portion arranged for attachment to a foot member of a prosthetic foot. A second end portion is arranged to extend freely over at least a portion of the top surface of the foot member. A second plate includes a first end extending over a heel member of the prosthetic foot and a second end extending over and attached to the second end portion of the first plate. The second end portion of the first plate situated between the foot member and the second plate. A pump mechanism includes a housing secured to the second plate and a membrane operatively connected to the first place and the housing. The pump mechanism defines a fluid chamber between a bottom surface of the housing and a top surface of the membrane.