Pressure Systems’ 116 and 126 (CS401 and CS406) have replaced the 169 and 173 Submersible Pressure Sensors (CS400 and CS405). The CS401 and CS406 can be read directly by the datalogger without the 7977 Resistor Assembly. The sensors feature strain gage technology and are designed for surface and groundwater level measurement. See www.campbellsci.com/water-level-stage-flow for more information on water level, stage, and flow sensors offered by Campbell Scientific.