A prosthetic system includes a prosthetic valve having a valve body with a shaft defining a flow channel fluidly connectable to an interior of a socket. One or more ports in the valve body are in fluid communication with the flow channel and a membrane is positioned in the valve body. A release button associated with the membrane controls allow air flow into the socket via the one or more ports while air can flow out of the socket via the one or more ports independent of operation of the release button. A one-way valve is connected to the valve assembly that selectively permit air flow out of the socket. A valve insert is mountable on the socket and arranged to couple the valve body to the socket. The valve insert defines an opening configured to allow the shaft to extend through the valve insert and into the socket.