Kit includes: 1 EZO-pH embedded circuit 1 Lab Grade Double Junction Silver/ Silver Chloride pH Probe 6x 20ml calibration solution pouches (2x pH 4, 2x pH 7 and 2x pH 10) 1x 20ml pH storage solution pouch 1 Electrically Isolated EZO Carrier Board New to electrochemical sensing? Don't worry, the Atlas Scientific EZO-pH Kit simplifies things. It includes all necessary components for accurate, interference-free readings. Once you're familiar, you can streamline your design and purchase only required components.