... , Auto-Buffer Recognition. 2, Message Indicator. 3, pH Range: -2.00~16.00pH; Accuracy: 0.01pH. Portable digital ph meter portable ... via the USB port.Specification: Model220221pH Range-2.00~16.00pH-2.00~16.00pHpH Accuracy±0.01pH±0.01pHmV/ORP RangemV ... ) or USA (pH4.01/7.00/10.01)NIST (pH4.00/6.86/9.18) or USA (pH4.01/7.00/10.01)Temperature Compensation0~100oC, 32 ...