TDS3 TEMP PPM TDS Meter Tester Filter Pen Stick Monitoring The Digital TDS 3 Meter is for testing water quality. Use the TDS meter to check the performance of your water filter. You can also check for hardness (1 grain = 17 ppm) Features: 1. 100% Brand New 2. This item can be used in: Read more about TDS3 TEMP PPM TDS Meter Tester Filter Pen Stick Monitoring[…]