Sping loaded check valves employ a spring pushing against a stem with a O ring which forms a seal at the seat of the valve internally. All check valves are directional with an aindicative flow arrow on the valve bodies. Some spring loaded check valves are Watermark approved to be used with portable water applicatins, whereas others may be general purpose only intended for irrigatoin or industrial uses. The spring loaded check valves come in diferent pressure and temperature ratings, where some high performance models can be used with solar and steam applications. As opposed to other check valves such as foot valves or swing check valves, the spring loaded check valves can be installed in any orientations when the other types are restricted.
