Fangrui Product Details Displays Tds Level Of Triple Water Line. Highly Efficient And Accurate Due To Its Advanced Microprocessor Technology. Auto-off Function Conserves Battery Power. The Unit Shuts Off Automatically After 10 Minutes Of Non-use. Wide Range 0-9990 Ppm (from 0 - 999 Ppm The Resolution Is 1 Ppm. From 1000 To 9990 Ppm, The Resolution Is 10 Ppm, Indicated By A Blinking X10 Image.) Factory Calibrated:our Meters Are Calibrated With A 342 Ppm Nacl Solution. Meters Can Be Recalibrated With A Mini-screwdriver. Trm1 Triple Tds Meter With Three Probes. Comes Equipped With Mur-lok Quick-connect T-fitting (1/4 Inch Standard, Also Available In 3/8inch Or 1/2inch ). Installs Quickly And Easily. Specifications: Range:0-9990 Ppm Accuracy: Conversion Factor:nacl (avg. 0.5) Cable Length:24.5inch (including Sensor) Fittings:1/4inch Standard, Also Available With 3/8inch Or 1/2inch Power Source:2 X 1.5v Button Cell Batteries (lr44 Or Equivalent; Not Included) Battery Life:. 1000 Hours Of Continuous Use Tips: The Product May B