1pc of PH tester. Accuracy: + 0.02 pH;. Resolution: 0.01pH;. Stability: ≤ 0.02 pH / 24 小时; ≤ 3 mV / 24 小时. pH standard solution: 4.00 / 6.86 / 9.18. That would be very appreciated. We must do our best.
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