5 year Limited Guarantee Bluelab Combo Meter The Bluelab Combo Meter is a portable Meter that takes measurements of pH, conductivity and temperature within a solution. The correct pH, conductivity and temperature levels of a nutrient solution is critical for healthy successful growth. 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. Features Measures pH, conductivity(EC, CF, ppm 500 and ppm 700)and temperature(°C,°F)Lightweight and portableLarge easy to read displaySimple push button pH calibrationSuccessful pH calibration indicatorNo calibration required for conductivity and temperatureReplaceable double junction pH probe includedOver range and under range indicatorsLow battery indicator2 x AAA alkaline batteries includedAuto off function "The Cadillac of Meters" It"s all you need for simple and reliable crop management The Bluelab Combo Meter has two probes, a Bluelab pH Probe and a Bluelab Conductivity / Temperature Probe. The Conductivity / Temperature probe is permanently fitted to the Meter, whereas the pH probe is replaceable. This is due to the fact that pH probes have a limited life and age through normal use. Replacement pH probes can be purchased separately. You can also connect a Bluelab Soil pH Probe to the Combo Meter to take direct pH soil measurements or measure the pH of a soil solution. The soil pH probe can also measure solutions. Bluelab Soil pH Probes can be purchased separately. Both probes require cleaning at least once a month and it is recommended to use the Bluelab pH and Conductivity Care kits. These care kits are made specifically for Bluelab instruments to increase probe life and ensure you are always receiving accurate readings. Large easy to read display The simplest Meter in it"s class When taking a reading, simply place both probes into the solution and the selected reading is displayed on screen. Both probes may be fully submerged into the solution. As the Bluelab Combo Meter is portable and does not require a power supply to operate, it can be used anywhere, anytime to help you manage your crops’ daily nutrient requirements. Calibration of the pH probe is simple and the instructions are supplied on the back of the meter. The push button calibration method makes this one of the simplest meters to use. Successful pH calibration indicators on the screen guide you through so you know the reading is reliable. After 30 days the calibration indicators will disappear, letting you know calibration is due. The Conductivity / Temperature probe does not require calibration as this is locked in during manufacture.