The ESSENTIALS pH Meter is truly an essential piece of equipment. It is water and drop resistant but must not be fully submerged. If accidentally dropped into water it will float so you can quickly take it out to avoid damaging the electronics. General Information For best results, we recommend calibrating this regularly to ensure a lifespan of 1 to 3 years depending on sampling rate. The energy saving feature will turn off the pH meter when not in use to save battery life. Benefits Easy to use Long life expectancy Accurately shows pH level How to Use Simply turn on and place the sensor inside your solution. When it beeps, the measurement can be read.