Pen pH Meters

Economy Pen pH Meter

Economy Pen pH Meter

Model: MA-257
Price: $61.00
Standard Pen pH Meter

Standard Pen pH Meter

Model: MA-258
Price: $104.00

Pen pH meters from Ohaus provide accurate, straightforward operation at an affordable price and are useful in the field or lab for soil classification and other applications. Units show pH measurements in the 0 to 14pH range on the large, easy to read LCD display. The pocket-size meters are constructed with a durable ABS housing, protective cap to safeguard the sensor, and automatic shutdown feature that preserves battery life. Pen meters endure prolonged use in rugged environments and feature IP67 waterproof design to prevent water damage. A wrist strap is included. The meters operate for approximately 200 hours on four included AG13 button-cell batteries. The working environment for both units is 50°F to 104°F (10°C to 40°C) and 85%RH, non-condensing.

MA-257 Economy Pen pH Meter has a range of 0 to 14x0.1 pH and accuracy of ±0.1pH. The built-in electrode is factory calibrated with no need for use of Buffer Solution, and the meter is not equipped with temperature measurement or compensation functions. Single-line LCD display.

MA-258 Standard Pen pH Meter range is 0 to 14 x0.01pH with ±0.05pH accuracy. The built-in electrode features 3-point calibration using 4.01, 7.00, and 10.01 Buffer Solution, available separately. This meter has temperature compensation with a range of 0 to 99.0°C (32.0 to 210.2°F). The dual display shows pH and temperature values.


  • Easy-to-read display
  • ABS housing
  • Automatic shutdown feature preserves battery life
  • IP67 waterproof design
  • Battery-powered

Included Items:

  • Economy or Standard Pen pH Meter
  • Four AG13 button-cell batteries
  • Wrist Strap


Power Supply Four AG13 button-cell batteries
Product Dimensions 1.8 x 7.3 x 1.5in (45 x 185 x 38mm) WxDxH
Estimated Shipping Weight 2.0lb (0.91kg)

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Power Supply Four AG13 button-cell batteries
Product Dimensions 1.8 x 7.3 x 1.5in (45 x 185 x 38mm) WxDxH
Estimated Shipping Weight 2.0lb (0.91kg)
Meets Standard(s):
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