Measurement Range:TDS: 0 ~ 9999ppm Pen type digital tds meter, all in one, tds electrode is included, FEATURES* 0 to ... 1.5 V battery (LR44) x 4 PCs* Pen type digital tds meter, all in one, tds electrode is included, easy for ... x 38 mm (electrode included).Weight82 g (electrode included). pen type ppm Meter