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Are you struggling to achieve accurate and reliable pH, conductivity, and salinity measurements in your laboratory or field studies?

The Ohaus Starter Pen Meter ST20M-C is your solution, bringing over a century of measurement expertise to your fingertips. This compact, all-in-one meter offers fast and precise readings across a wide range of water quality parameters, making it an indispensable tool for any serious lab or environmental professional. Engineered by Ohaus, a trusted name in laboratory instruments, this pen meter seamlessly combines functionality with simplicity for hassle-free operations.

Key Benefits:

  • Versatile Measurements: Accurately gauge pH, conductivity, salinity, temperature, and more with a single device.
  • High Precision: Enjoy the confidence of reliable results with an accuracy of ±0.05 pH and ±0.5 °C, ensuring your data is always trustworthy.
  • Rugged Design: Constructed with a durable ABS housing and an IP67 waterproof rating, it is built to withstand harsh laboratory and field conditions.
  • User-Friendly: Features like a clear LCD, automatic shut-off, and replaceable electrodes make operation and maintenance straightforward.
  • Portable Convenience: Its compact, lightweight design and included wrist strap make it easy to carry, reducing the risk of accidental drops and ensuring measurements can be taken anywhere.
  • 5-Year Warranty: Enjoy peace of mind and long-term reliability with a comprehensive 5-year warranty on your investment.

When you choose the Ohaus Starter Pen Meter ST20M-C, you're not just getting a tool but adopting a seamless and stress-free way to conduct water analyses. Feel empowered knowing you have a reliable, accurate, and easy-to-use meter, enhancing your capabilities and efficiency in water quality testing. Experience the peace of mind from knowing your precise measurements, allowing you to focus on what truly matters in your research and analysis. Equip your lab with the power of Liberty Scales' endorsed laboratory instruments and see the difference in every drop you analyze.

Reach out to our dedicated team for further information and personalized assistance. Call us at (661) 888-1919 or email us at We're here to help you every step of the way!

  • Meter Type: Conductivity; pH; Salinity

  • Measurement Range: 0.0 – 10.0 ppt; 0.0 – 99.0 °C; 0.00 – 14 pH; 0.00 – 19.99 ms/cm

  • Accuracy: ±2.0 % F.S.; ± 0.05 pH / ± 0.5 °C

  • Measurement Resolution: 0.1 °C; 0.1 ppt; 0.01 pH; 0.01ms/cm

  • Display: LCD

  • ATC: Yes

  • Temperature compensation: Not Applicable

  • Automatic Shutdown: Yes, After 6 minutes of non-use

  • Battery Life: 100 Hours with Disposable Batteries

  • Calibration: 3 Point

  • Conductivity accuracy (±): 2 %

  • Conductivity measuring range: 0.00 – 19.99 mS/cm

  • Dimensions: 1.5 in x 7.28 in x 1.77 in (38 mm x 185 mm x 45 mm) (LxHxW)

  • Net Weight: 3.88 oz (110 g)

  • Number of Buttons: 3

  • pH accuracy (±): 0.05

  • pH measuring range: 0 – 14

  • Power: 4 AG13 Batteries (Included)

  • Protection Rating: IP67

  • Temperature Display: Yes

  • Temperature Sensor: 50 KΩ NTC

  • Working Environment: 50°F – 104°F, 85%RH, non-condensing (10°C – 40°C, 85% RH, non-condensing)

  • Wrist Strap: Yes
  • Free Shipping: Available across 48 continental USA. Extra charges may apply for residential, farm, or rural areas.
  • Express Shipping: Overnight and faster shipping options available at additional costs. Quotes obtainable via email.
  • Delivery Time: Typically 5 to 7 business days, varying by location and external conditions.
  • Tracking Information: Provided via email upon shipment. Accessible through account login. Additional information available upon request.
  • Return Policy: 15-day return period for unused, original condition products. A 25% restocking fee applies. Buyer covers original and return shipping costs.
  • Customer Support: Contact at (661) 888-1919 or for queries or concerns about shipping.