We are using a switch that has single-point level indication/Control combined with a switch that has a constant level output. Checkpoint, Radar, and NINA are three such single point level indicators/Control switches. Ultrasonic, Pressure, and Capacitive switches are constant level output types. These two technologies combined add additional layers of protection for operating pumps, valves or just level indication with control points. For example, if a Checkpoint sensor and a pressure switch sensor are combined the best of both will be clear. This combination is a single point switch control (Checkpoint) and a variable output switch (pressure transducer) to read the level and activate switches at different levels to perfect the controls. They work independently from each other so if one fails or goes out of calibration or gets debris lodged in it then there is now the ability to question the one that seems inaccurate, long before a catastrophic failure.