Soil Moisture Sensor Meter with Light & pH Acidity Tester 3in1 Gardening Hydroponic Tool Analyzer for Indoor/Outdoor ,No Battery Needed Simple and convenient to use.Insert probe of the meter into the soil, switch to the setting you want to measure and read the scale Scientifically Accurate: Easy to read moisture, ph and light levels, promotes healthy plants Let you know when to water.Help you to control Ph level in soil, acidic or alkaline is suitable for your plants .Help you to determine if plant getting adequate light. 1.Without touching the stone, don't too hard, easy to damage the probe 2. After using, need to clean and wipe the probe (can't test the water) 3. Don't inserted in the soil for a long time for using Compact and portable design for indoor/outdoor use.Pin length:7.8-inch,total length:10.8-inch