7 in 1: The water quality test pen is a 7 in 1 style. Salinity salinity 0.01-20.00%; suitable intake salinity value for human body is 0.900%. Function: PH, TDS, EC, salinity, ORP, temperature, SG. The specific gravity of S.G seawater is 1.000-1.222; the density of seawater in different regions is usually 1.02-1.07, and the weight of Rongjie salt is about 3.5% on average.
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