The Ohaus ST3100MF Starter 3100M with ST3100M-B content; ST310, STCON3, pH Powder Sachet Set, 1413 uS/cm & 12.88 mS/cm solution (20ml bottle), helps you save time, space and money, which combines all your pH, ORP, conductivity, TDS, salinity, resistivity and temperature measurements - in one smart device. Ideal for a wide range of lab applications, the ST3100MB is incredibly easy to use. Equipped with software to ensure the reliability of your readings, and RS232 connectivity to store and transfer data conveniently, the ST3100MB is a great addition to your lab.