The Ohaus ST270 is a Glass spear pH Electrode, sensitive from 0.00 - 14 pH. The puncture electrode suitable for semi-solid samples such as fruits, meat or cheese. The Ohaus Starter Series of electrodes are designed to produce exact results time and time again. The Starter Series includes pH, reference, oxidation-reduction potential (ORP), conductivity, dissolved oxygen (DO), and temperature electrodes that can be used in combination with Starter bench and portable meters. The ST270 is compatible with the Ohaus Starter line of Portable and Bench pH Meters.