Oxygen Free Preservation
Each enclosure has two stainless steel one-way valves. A one-way valve is sometimes called a check valve, lets gas flow in only one direction. They are rated for a very low breaking force. Breaking force is the amount of pressure needed to open the valve and allow the flow of gas or liquid. Since Argon is heavier than air the inlet valve is lower than the exhaust valve to allow a better flushing action of the contents of the enclosure when the top(head) of the enclosure is raised slightly during the gas replacement process.