HM DIGITAL INLINE TDS METER, MARINE AQUARIUM, RO WATER, REEF, MONITOR, CORAL SM1

Inline TDS Monitor. For inline testing of RO water from your RO unit. 7.6 x 2 x 4.7 cm (3 x. 8 x 1.9 in.). Specification Range Power source Battery life 2 x 1.5V button cell batteries (LR44 or equivalent; included).

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