| Model | 8551 |
| mV Measuring Range | -1999~1999 mV |
| mV Accuracy | ±0.2 mV (-199.9~1999.9 mV) or ±2 mV (others) |
| mV Resolution | ±0.1 mV (-199.9~1999.9 mV) or ±1 mV (others) |
| Temperature Measuring Range | 0~60.0℃ |
| Temperature Accuracy | ±0.3℃ |
| Temperature Resolution | 0.1℃ |
| pH Calibration | Up to 5 points |
| 99 points memory | YES |
| Real Time Clock | YES |
| Compatible Probe | ORP: 850PAZ, 86P5AZ |
| LCD Size | 44(L) * 26(W) mm |
| Operating Temperature | 0~50℃ |
| Operating RH% | Humidity <80% |
| Storage Temperature | -10~50℃ |
| Storage RH% | Humidity <90% |
| Sensor Life Time | >6 months (with good maintenance) |
| Meter Size | 175(L) * 70(W) * 33(H) mm |
| Weight | ~150g |
| Battery | AAA *4 PCS |
| Standard Package | Meter, Batteries, Manual, Carry Case, Calibration Solution |
| Optional Accessory | USB Cable & Software |