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Are you facing challenges in obtaining precise and quick measurements for water quality and composition?

The Ohaus Starter Pen Meter ST20R, brought to you by Liberty Scales, is your perfect solution. This compact, ORP-type meter is specifically designed to deliver accurate readings across a variety of parameters including pH, temperature, conductivity, salinity, and total dissolved solids. Ideal for laboratory instruments and field applications, this meter simplifies complex measurements with its user-friendly interface and robust features.

Key Benefits:

  • Wide Measurement Range: Accurately measures from -1000 to 1000 mV and temperature from 0.0 to 99.0 °C, ensuring versatile applications in any water analysis scenario.
  • High Accuracy: With an accuracy of ±2 mV / ±0.5 °C, it guarantees precise readings, crucial for reliable water analysis, meter, and electrode tasks.
  • Durable and Portable Design: The ABS housing and IP67 waterproof rating make it suitable for use in rugged environments. Its compact design fits easily in your hand, allowing for on-the-go measurements.
  • Ease of Use: Features like the automatic shut-off and easily replaceable electrodes enhance user convenience, making it ideal for continuous, everyday use.
  • LCD Display: Comes with a clear, easy-to-read LCD display that provides secondary information, facilitating better data management.
  • 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 ST20R, you're not just purchasing a tool; you're investing in reliability and efficiency. Imagine the peace of mind you'll have knowing that your water analysis is backed by the precision of Ohaus and the expertise of Liberty Scales. This starter pen meter not only elevates your laboratory capabilities but also ensures consistent, dependable results that you can trust. Embrace the simplicity and proficiency of the Ohaus Starter Pen Meter ST20R—because accuracy matters in every drop.

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: ORP

  • Measurement Range: -1000 – 1000 mV; 0.0 – 99.0 °C

  • Accuracy: ± 2 mV / ± 0.5 °C

  • Measurement Resolution: 1 mV

  • Display: LCD

  • ATC: Yes

  • Temperature compensation: Automatic

  • Accuracy ± (mV): 2 mV

  • Accuracy ± (Temperature): 0.5 °C

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

  • Battery Life: 200 Hours with Disposable Batteries

  • Calibration: NA

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

  • Measurement Range (Temperature): 0 °C – 99 °C

  • Measurement Range: -1,000 mV – 1,000 mV

  • Net Weight: 3.88 oz (110 g)

  • Number of Buttons: 2

  • Power: 4 AG13 Batteries (Included)

  • Protection Rating: IP67

  • Temperature Display: Yes

  • Temperature Range: 0 °C – 99 °C

  • 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.