Frequency: 128Hz / 111Hz/ 105Hz/94Hz/AFC ± 1Hz. Digital earth resistance / Soil resistivity tester ST2306 4 pole ,Soil resistivity : 0.06~19.99KΩ;±(2.0%rdg + 3dgt). 2 pole & 3 pole: 0.01~19.99KΩ;±(2.0%rdg + 3dgt).
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