Accurate (within 0.2) large display readings of pH level in liquids eg fish tanks, swimming pools. Comes with 9V battery and initial buffer solution - we stock refills of buffer solution. Calibration tool included. Extendable probe makes this easy to use. Operates in range 0 to 50 C , reads pH 1-14 - all you'll ever need. 158 mm H x 40 W x 34 D.