3. Lock button: After the value is stable, click the hold button to lock the current value. If you need to re-measure, please press the hold button again. Features:1. Backlight design: Large LCD screen design with backlight for clear display and more convenient to read. Insert the electrodes of the tester into the soil and waited for a few seconds to get the data on the LCD screen. 2. Highly sensitive probes: Adopting alloy electrodes for higher sensitivity and durability. Turn on the tester, insert the probe into the soil for 5cm and the measurement data be displayed after about 3 seconds. Wipe the electrode after measurement to keep it clean. 4. Wide range of applications: Can be used for Potted planting, Scientific experiment, Orchard planting, Grassland and pasture, Agricultural planting, etc., Weight: 1.8518830008 pounds, Manufacturer: Kueohse