PH 4.01/7.0/10.01 Buffer Solution Set 150ml Calibration Fluids Aquarium PH Meter

PH 4.01 ( ±0.02 / 25 ℃ ) buffer solution 150ml X1. PH 7.00 ( ±0.02 / 25℃ ) buffer solution 150ml X1. PH 10.01 ( ±0.02 / 25℃ ) buffer solution 150ml X1. The reference reading of ORP should be between -190 and 50mV.

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