【10M-300M WELL WATER DEPTH METER】Achieve meticulous accuracy with our deep well water level meter, the measurement unit is centimeters, the minimum reading can reach 1 mm, and the repeatability error is ≤ 2 mm,the Probe is depth up to 300m(984ft), and the applicable temperature of the instrument is -20℃--+60℃, ideal for measuring well levels. 【BATTERY POWERED】The groundwater levels gauge is powered by a 9V battery, which is convenient for construction and portability, and saves the trouble of connecting another power cord(Package not include battery).Well Water Depth Meter Indicator are available in various sizes:10m, 20m, 30m, 50m, 100m,150m, 200m, 250m, 300m. Please confirm the correct size for your needs before purchasing. 【0.99IN STAINLESS STEEL PROBE】Steel ruler water level gauge featuring a robust stainless steel probe, this device activates upon water contact via water-resistant points, triggering the peak display and indicator light. The probe uses a larger 0.99-inch (25 mm) diameter probe for easy removal and cleaning. 【ERGONOMIC DESIGN】Standard reels are ergonomically designed for good balance and ease of use, with a stand-alone design, convenient carrying handle and an excellent brake. They are robust and smooth running. The battery is housed in a convenient battery drawer and each reel has a probe holder and brake. The reels are equipped with an on/off sensitivity control, light, buzzer and a battery test button 【VERSATILE APPLICATIONS】Steel Ruler Water Level Meter provides a most accurate way to measure water levels. The meter is commonly used to measure the water level in wells, boreholes, tanks and Water-Pipes, particularly suitable for the observation of groundwater level in hydro power projects and inspectors who inspect dam body infiltration line. Not only be used during construction but also as a long-term safety monitoring for a project.