These pressure transducers are rated IP65. They are all stainless steel. Pressure Transducers measure water pressure while submerged in a water reservoir. When they are fully submerged in the bottom most depth of a given water basin, they will give an accurate measurement of the depth of water in terms of a 4-20mA current output. A 4mA signal would be indicative of a pressure transducer with no water covering it. A 20mA current would be measured when the pressure transducer is covered with a height of water equivalent to its maximum rating. The depth of the environment must be a known variable in sizing the sensor correctly. Pressure transducers are also available with a 0-10V output.