YSI ProSwap [626700-2] Digital Water Quality Meter With GPS. The YSI ProSwap Digital Water Quality Meter allows you to swap one smart sensor for another. Featuring built-in temperature and optional depth sensors, ProSwap can transform into whatever you need. The ProSwap is a purpose-built turbidity meter, high-accuracy optical DO meter, spot sampling pH meter or a profiling conductivity-temperature-depth system. Connect any ProDIGITAL integrated probe/cable assembly to the ProSwap handheld or any ProDSS digital water quality sensor to the ProSwap cable. Sensors and cable assemblies are user-replaceable with cable lengths ranging from 1 to 100 meters. The ProSwap incorporates smart sensor technology that enables sensors to be automatically recognized by the handheld. Additionally, DIGITAL sensors store calibration data, so probe assemblies can be swapped between handhelds without the need for re-calibration.