... type digital tds meter, all in one, tds electrode is included, FEATURES* 0 to 9999 ppm* LCD indicates both ppm & Temp.* Auto ... battery (LR44) x 4 PCs* Pen type digital tds meter, all in one, tds electrode is included, easy for ... FTDS Calibration6640 ppm , 1 point calibrationOperating HumidityLess than 80% RHDimension188 x 38 mm (electrode included).Weight82 g (electrode included). low price ppm Meter