Waterproof pocket-sized pH meter with advanced micro-electronic sensors. Features unbreakable non-glass silicon micro sensors, on chip temperature display, displays both pH and temperature, measure samples as small as one drop. Stable readings in seconds, convenient one-point calibration, automatic temperature compensation, automatic buffer recognition, over 150 hour lifetime on one single watch battery, automatic power off and comes with error message alerts for incorrect calibration situations and meter failure. Accessories kit includes users manual, pH 7 standard solution and carrying case. The S2K712 has been replaced with S2K222.  Reference Electrode R2K712 can be used with S2K222