This is the Accurate pH 2. This meter is a step up from Control Wizard Products' Accurate pH 1 meter with readings that show pH in whole and tenths of a pH point. It has a two-point calibration process that is easy to do and takes little time. This calibration process requires the pH 4.0 and pH 7.0 calibration solutions (Sold Separately). It has a temperature compensation feature and a large display that can be easily seen in lowlight situations. The meter is attractive and fits comfortably in your hand.The Accurate pH 2 and Accurate PPM 2 share housing styles for those growers who prefer a matched set. It comes with a plastic case, screwdriver and instructions. This meter comes with a limited one-year warranty with your original sales receipt. The Accurate pH 2 uses four (4) LR44 batteries.