Lift-check valves feature a guided disc and a similar seating arrangement as globe valves. They are best used in systems with globe valves and plastic check valves. There are three body patterns (horizontal, angle, and vertical) which can be installed in horizontal or vertical lines with upward flow. For proper function of lift check valves, the flow must enter below the seat. The pressure of the upward flow raises the seat within guides from the seat. The disk falls back down to close the pipe when the flow stops or reverses. When installed horizontally, the disk is suspended by a system of guide ribs.