Solinst Model 201 [113415] Water Level Temperature Meter with 5/8" Probe & Metric Increments, 250m. The Model 201 Water Level Temperature (WLT) Meter is ideal for measuring static water levels, as well as profiling temperature in wells, boreholes, tanks and open water. Accurate temperature measurements are clearly displayed on an LCD readout on the faceplate, from -20ºC to +125ºC. Water level and probe depth measurements are read off the Solinst durable PVDF flat tape. Tape lengths are available up to 1000 ft (300m). The 201 Probe is made of high quality 316 stainless steel. The pressure-proof probe can be submerged to 1000 ft (300m). The zero measurement point on the probe is close to the tip, keeping water displacement at a minimum. The temperature sensor is located at the stainless steel tip of the probe, however, since the probe body acts as a heat sink, best accuracy is obtained when the probe is completely submerged. The tape seal plug design allows the probe to be easily replaced, if required. The WLT Meter uses extremely durable PVDF flat tape. The tape is non-stretch and has a dog bone design that prevents adherence to wet surfaces. The tape reels smoothly, remains flexible and hangs straight, regardless of temperature. It is also easy to repair and splice. The 3/8" (10mm) wide tape has permanent laser markings every 1/100 ft. or each millimeter, traceable to NIST and EU measurement standards. When the meter is turned on, the LCD screen displays the firmware version of the WLT Meter (e.g. “WLTM 1.0”) for about two seconds. The LCD will then display the temperature reading, in or out of water. The LCD menu is simple to operate. Pressing the button two times quickly deactivates the buzzer (the light stays active). To reactivate, press the button two times quickly. To turn the meter off, press and hold the button for two seconds. When the zero point of the 201 Probe enters water, an electric circuit is completed, activating the buzzer and light. The depth to water is then read off the flat tape. Temperature readings are read off the LCD display. As the probe is lowered to take temperature measurements at discrete depths, the buzzer can be turned off by pressing the button two times quickly. This is ideal when profiling temperature.