Digital Aid Professional TDS, EC & Temperature Meter. 3 in 1. Professional Quality TDS Meter:0-9990ppm. Accurate and Reliable Water Test Meter. Ideal for Drinking Water, Aquariums. With Leather Case. $13.97 B00HAKAFGC
TDS - Best Water Quality Test Meter. Large Backlit LCD Screen. Professional TDS and Temperature Meter at an Economy Price. on this Accurate and Reliable Water Test Meter. $14.47 B00O0FJNAO
Digital Aid pH Calibration Solution Powder (4.00pH, 6.86pH, and 9.18pH). (1x3 Pack)(FBA) $5.95 B00PG1RFLK
Digital Aid pH Meter. Professional Quality Water Test Meter by Large Backlit LCD Screen. Range 0.00 to 14.0 pH. 3 Free Buffer Solution Powders. Plus get 6 More - See Below. $14.87 B017J5GQHY