Connections are made to the back of the Reserator XT by way of two industry standard CPC quick-disconnect fittings that incorporate internal check valves. Having check valves is convenient as they block off flow as soon as the connection is broken and keeps any spillage to a minimum. In high-flow systems, integrated check valves can create significant flow restrictions but in a low-flow system like the Reserator XT, that isn't as much of a problem and the added convenience is well worth it.