Milwaukee MW151 Max Logging
The most accurate meter here, for labs that need 0.001 pH resolution and full logging.
Amazon $538.20$538.20
±0.002 pH5-pointNone
3.6/5
A lab bench meter with proper record keeping, for QC labs that need to export readings.
- ±0.01 pHAccuracy
- 3-pointCalibration
- IP54Waterproof
- YesReplaceable probe
Check price at Amazon$395.85
Price checked November 8, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Stores 500 readings and exports them over USB for lab records
- Shows electrode slope so you know when a probe is wearing out
- Three-year meter warranty
Cons
- Three-point calibration only
How it scores
The rating comes from 6 measured or published factors, each scored 0-100 against fixed reference points for its type. How we rank explains each one.
Specifications
| Model number | AI521 |
|---|---|
| pH measurement | |
| Accuracy | ±0.01 pH |
| Resolution | 0.01 pH |
| Range | -2 to 20 pH |
| Calibration | 3-point |
| Temperature compensation | Yes |
| Other readings | |
| Conductivity (EC/TDS) | No |
| ORP | No |
| Salinity | No |
| Build | |
| Replaceable probe | Yes |
| Waterproof rating | IP54 |
| Stored readings | 500 readings |
| Connectivity | USB |
| Meter warranty | 3 years |
| Probe warranty | 6 months |
Alternatives in this type
Apera PH700 Benchtop
An affordable starter bench meter for school labs, breweries and small QC benches.
Amazon $299$299
±0.01 pH3-pointNone
$205
±0.01 pH3-pointNone
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