HM Digital DM-1 Inline Dual Probe TDS Meter -MTR-TDS-DM1

In-Line Dual TDS Monito r The DM-1 is consumer friendly monitor measuring feed (input) water vs. product (output) water of a water filtration system at any time.

 dual TDS meter post membrane and post DI stage. These two readings will notify you when it's time to change the RO membrane and DI resin.