The Ulti-buoy with Cellular or Satellite telemetry, S9 inductive modem technology, and XT/XTP sensors enables reliable, low cost, high-accuracy monitoring in fresh or salt water up 200 meters depth. New hull options range from 30 to 60 cm diameter, allowing a greater range of applications and sensor payloads. The buoys are easily deployed/recovered from a small boat, fully submersible to 15 meters, and support up to 20 sensors at user-adjustable depths. XT/XTP sensors can sample up to every ten minutes for three years without service. Third party sensors for Conductivity, DO, and other parameters are also supported. From single or multi-depth water quality monitoring applications to relaying data from bottom mounted instruments via Iridium or Cellular telemetry, Ulti-buoy solutions offer superior value.