Bluelab pH Meter The Bluelab pH Meter is used to accurately measure the pH value of a solution. Simply place the pH probe into the solution and the reading will be displayed on the screen. As the meter is portable and does not need a power supply to operate, it can be used anywhere and anytime to help you manage your crops' daily nutrient requirements. It is easy to calibrate by using the push buttons on the meter and fresh Bluelab calibration solutions. Supplied with standard Bluelab pH probe, solutions (sachets) and batteries. Range: 0.0 – 14.0 pH. Resolution: 0.1 pH. Accuracy @ 25°C: ± 0.1 pH. Power Source: 2 x AAA. Features: auto turn off, low battery indicator, over range and under range indicators, portable. 5 year Bluelab Guarantee.