pH Meter 4 in 1 PH Light Moisture Acidity Te ster Soil Te ster Moisture MeterDigital 4 in1 Soil PH Te ster Water Moisture Light Sunlight Test Meter For Garden Plant Flower Acidity Moisture Measurement Tools 1. Don't use it to test liquids. Used to test soil only. 2. Install the battery and remove the probe cap before use (9V battery is required) 3. After using it for a period of time, the screen will only show the green screen instead of the number, That means the battery is dead. (There is no need to worry about damage to the