HI 98129 Pocket Meter
Hanna Combo Pocket Pen
The low range Combo pH, EC, TDS (ppm), and temperature meter is one of Hanna’s most popular meters. The waterproof design, simple operation, and replaceable electrode mean that you can rely on this meter for years.
pH Range: 0.00 to 14.00 pH
EC Range: 0 to 3999µS/cm
TDS Range: 0 to 2000 ppm
Features:
- 1-point conductivity calibration
- 1 or 2-point pH calibration
- Battery life = 100 hours
Resources:
Calibration information 
YSI Pro 20