TDS-3 Portable 0.9" LCD Water Quality Tester Pen - Khaki (2 x LR44)
Measurement range: 0-9990ppm - Temperature range: 0~80'C - Accuracy: +/-2% F.S - Application: Water quality testing tap water purified water mineral water meets drinking water standards measurement - Please well noted that the TDS pen can not use to measure high temperature water or high speed flowing water.