Combo Meter pH, EC and temperature measurement The Bluelab Combo Meter is a portable all in one pH, conductivity and temperature meter. If you are experiencing problems with yellow leaves, or slow stunted growth, the Bluelab Combo Meter will soon tell you if each parameter is within the plants requirements. Adjustments can be quickly made to get your crop back on track. The Bluelab Combo Meter has two probes, a Bluelab pH Probe and a Bluelab Conductivity/Temperature Probe. When taking a reading, simply place them into the solution and the selected reading is displayed on screen. As the Bluelab Combo Meter is portable and battery operated, it can be used anywhere, anytime to help you manage your crops daily nutrient requirements. Calibration of the pH probe is simple, as instructions are supplied on the back of the meter and the easy push button method makes this one of the simplest meters to use. The pH probe is replaceable so you can use this meter for years to come. The conductivity/temperature probe does not require calibration as this is locked in during manufacture. Measures pH, conductivity / nutrient (EC, CF, ppm 500 and ppm 700) and temperature (°C, °F) Lightweight and portable Large easy to read display Simple push button pH calibration.