The higher ppm value is,the more substances in the water. Factory calibrated,widely apply to test water qulity,for RO system, aquariums, hydroponics, pools, spas,etc.
Dual Range:measures from 0-999 ppm,with resolution of 1 ppm;from 1000-9990 ppm,resolution is 10 ppm,indicated value x 10.
LCD Display Screen Size:20 x 8 mm / 0.79 x 0.31 inch (L*W); Overall Size : 155 x 30 x 24 mm / 6.1 x 1.18 x 0.94 inch (L*W*H).
Package Content :1 x TDS Tester; Each meter included: 1 x Leather Case and 2 x 1.5V Button Cell battery (included).